Greg,
?

That doesn't sound correct to me at all.......I've looked at dozens of BowTech BC's and what you are saying just doesn't make any sense.

First off........I find it odd that all 3 shipped at 71.2#'s? I have 3 different BC's at home right now, and they read, 71#, 70.8#, and 71.1#.
I guess it's POSSIBLE, but the speeds you are stating for those draw lengths wouldn't be on those certificates.

The range for the MM at various draw lengths should read pretty similar to this:
30"= 314-322
29"= 304-312
28"= 294-302
27"= 284-292
**These are just approximates**.

You will probably see a little bit of a change in ratio as you increase draw length but these should be ballpark.
What I mean is that you might have only an 8fps jump from 27" to 28", but you might see 10fps from 29" to 30". It's close, but I have seen the greatest speed jumps when you hit the highest module for any given model.

Anyway, your bow at 27" and 287fps falls right in the speed range I listed.

The others you mentioned would not make the speeds listed and would not ship.
I could possibly see if you had a speed rating where 2 different draw lengths are close to overlapping.......say like a 28" at 292fps (Low end)and maybe a 27" @ 292 (extreme high end)
But what you are saying doesn't jive.

One thing I HAVE seen on these BC's is poor handwriting. Are you sure that you saw what you saw? IS it possible that you just read them quickly?
I'm curious as to this because it basically makes no sense at all, and I'm a BowTech guy.
Can you get your hands on these again and write down the exact numbers again for curiosity's sake?