Once again, here is my explaination for this regurgitation method:
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To me, this regurgitation is just an alternative "face-hugger" and an interesting survival method. When the Queen is young and not ready to reproduce the masses of eggs through an egg-sac (and assuming there are no other Alien warriors around, at the time), the Queen will run around and quickly plant hosts with embryos that are probably in much more advanced stages, than face-hugger embryos, thus the embryos that are regurgitated will burst faster. The face-huggers have a slower process of "impregnating". but there will MORE of the face-huggers, when the eggs are layed, of course.
So, once the Queen has enough warriors to help construct a hive, she goes into hiding within the hive and matures, thus she becomes full-grown, produces an egg-sac and starts to produce the hundreds to thousands of eggs, which do the process at a slightly slower pace, but at a much grander scale.
Now, when the Queen is running around "regurgitating" the embryos, I think the process of the embryo being created inside of her will be faster than a facehugger, but the time in between the creation of the embryos will probably not be in a matter of minutes, but certainly not as long as human pregnancy, for example.
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I also want to add that I don't think the PredAlien "vomits" (not like the Excorsist), but mainly passes the embryo (maybe, just like the face-hugger, or the chestburster might be more developed and we see the burster body go from one mouth to another).
Speaking of which, anyone recall the Alien 3 comic series, which showed the Queen chestburster climb out of Newt's mouth and climb into Ripley's mouth, after the crash?
On a related subject, there was a movie, which had these alien creatures control humans, by crawling down the human mouths...I can't remember the name of it. I think there was a sequel made. Anyone know what movies I'm talking about? The creatures could go from one host to another, by crawling out of the hosts mouths and go into another human mouth. The creatures were kind of like slugs, if I remember correctly.