Actually, if the SJ's are ASEXUAL, as are the Xenos, there is no reason to assume they would understand human reproduction and if they are exploring biomechanics then these experiments make perfect sense. Also, how can it be odd to you that an intelligent creature not be able to understand an organism's lifecycle just by looking at it. Are we to assume the humans are ignorant in ALIEN? Because thats exactly what happens in ALIEN. In many ways that script isvery complimentary to alien... I agree 100% that it is a smart direction to take.
In answer to your first sentence...
we (intelligent humans) have been able to use modern science (especially Biology, Molecular Biology and Chemistry) to fundamentally understand the mechanism(s) of replication/reproduction across the diverse panalopy of terrestrial, organic Life. We don't reproduce asexually, but that hasn't stopped us from determining the methods and mechanisms employed by the countless organisms on Earth that do reproduce asexually. Nor has it prevented us from understanding the life cycle of inumerable organisms that, from our perspective, are bizarre and quite "alien". Furthermore, our knowledge encompasses the entire hierarchical levels in which Evolution works, from demes, to individual organisms, all the way down to the level of genes.
As to the rest of your reply...
My post was specifically targeted at the "Alien Harvest" script, so your discussion of the Nostromo team in the original "Alien" movie is besides the point. My argument was/is that the Space Jockey race, as depicted in "Alien Harvest", is counter intuitive to what we would expect of an intelligent, technological race.
However, since you did bring up the humans on the Nostromo...
The Nostromo's science division (Ash) was able to learn quite a bit about the Alien, despite only having a dead face hugger to study...e.g. outer layer of protein polysaccharides, it replaced it's cells with "polarized silicon", it's structure allowed for prolonged survival in adverse environmental conditions, etc. And that is just the stuff that Ash disclosed to Ripley. We (the audience) are given the implicit impression that Ash also knew that the facehugger had "impregnated" Kane with it's offspring, and that something bad was going to happen to Kane when the offspring gestated. Ash saw the "stain" on Kane's lung during the bio-scan, and evidentlly could put 2 and 2 together. If you watch the chestburster scene carefully, you see Ash being strangely observant of Kane, even before he goes into seizures. Ash also is the one who recommended fire (hence the flame-throwers) as a possible weapon against the Alien. So, while the regular crew may have been more or less clueless with regards to the Alien, the Science Officer certainly had "collated" quite a bit of salient data on the creature...and in a remarkably short period of time.
Yet, in "Alien Harvest", the Space Jockey's are either incredibly dumb, or incredibly lazy (or perhaps both). Despite having multiple human specimens to analyze and observe for an extended period of time (at least months, possibly years), they resort to MIND CONTROL (mental telepathy, I kid you not) in order to induce one specimen to insert his reproductive organ into another specimen's waste canal. Yeah, as if utilizing a waste canal as a locus for embroynic incubation could possibly be a successful evolutionary reproductive strategy. Apparently the Space Jockey's were interstellar engineers...but "rocket scientists" they were not.
Well, let me first say that I admire the breath of your respnse to me, but it is precisely because you display insight into science and evolutionary theory that makes me call your bluff. Certainly someone with your know-how realizes that the problem with the reasons you propose HARVEST is silly are steeped in a narrow global-centrism. There is no science to why an Intelligent Alien life who has evolved x% differently than humans should present tarits that imply what you call "intuitive to what we would expect of an intelligent, technological race" Why should they? They have no evolved the way we have. This is just as incorrect as you saying that if you dropped the same proto-organisms off on 2 different planets, they would eveolve the same way based on two completely different model enviorments. Plus, in the first film ALIEN, the SJ's ALREADY don't appear to have evolved in a way we can intuitively understand. You are talking about a script that exists within a larger series of films that does not present any of it's creatures as having any relationship to our knowledge of Evolution as we are only familiar with the way organisms have eveolved on THIS planet. Anyone with less than a narrow concept of evolution and science (and that is YOU) would know that these creatures, traits would have to reflect their enviornment and you are suggesting that it is lazy based on the evolutionary laws ON EARTH. These creatures may not even be from another planet. The movie is called ALIEN for a reason. We dobn't know how they evolved. Thats why they are ALIEN TO US. Surely anyone willing to accept the mere idea of an Alien race's evolution would HAVE TO know that if these life forms would most likely be subject to entirely different evolutionary laws. That said, none of the species the ALIEN series presents suggests any reason to assume their natural enviornment could or would be similar to ours. IN fact, if anything (and this is a much larger discussion) the Xenos and Space Jocjeys in ALIEN alone suggestively have evolved quite differently. If you take HARVEST into consideration, along with ALIEN, the Alien does not appear to see and yet it appears to intuitively camoflage and have some sort f concentrated acid for blood... You're logic, while impressive would make lots of other things you've ALREADY accepted in the other films, also kinda silly. You cannot INTUITIVELY UNDERSTAND an organism that's existence has never been encountered. You also cannot really assume much about what the SJ's know or are doing because NONE OF IT, EVEN IN ALIEN, follows our Earthbound evolutionary laws. Aside from that you know the age old ARTHUR CLARKE quote comes into play. He said "Any sufficiently advanced technology is indistinguisable from magic." That certainly applies to the SJ's in ALIEN and in HARVEST.
For sure you realize that the whole idea of the perversties presented by the ALIEN races in these films is that they must have evolved differently. That said, there is nothing about the way the SJ's are presented in HARVEST to suggest that they have evolved similarly or in an environment that is ANYTHING like the planet earth. Unless you think the planet in Harvest is meant to be their homeworld, and it doesn't seem to be. It seesm to suggest that they are HARVEST-ing on a terraformed planet.
LSS, the SJ's do not appear to have come from an enviornement that is in any way similar to our own, and I don't think this idea has been lost on you. You seem to have a good understanding of Evolutionary Theory. It is ridiculous to turn around after ALIEN and state that the creatures should be more plausible as we would expect Earth Creatures to be when the whole idea to begin with is something that scientifically does not make sense.
FURTHERMORE, you have also suggested that these INTELLIGENT BEINGS should be abe to understand different reproductive cycles. A good point! But this is also based on the baseless assumption that on there planet the same reproductive systems exist as do on earth and even more so, you assume that ON EARTH all scientists should be and ARE familiar with the varied reproductive cycles of all species. This is silly. I hear about new reproductive cycles ON EARTH quite remarkably sometimes. Have you ever seen how Leopard Slugs reproduce?
So why should the SJ's understand every possible reproductive cycle in the universe unless they are previously familiar? You also mentioned that they had time to study us, but there is nothing in that script to support that. There is nothing in that script to support them doing much of anything. They are in fact, quite mysterious. There is little to nothing explained about what they do or why.
Not THE LEAST OF WHICH is whether or not the mind control worked. As one brilliant fan proposed. There is nothing in that scene to demand that the audience can be sure the 'mind control' wasnt simply an excuse for the two to get it on. Yet another brilliant and subtle ambiguity in that script, I think.