i know from my experience of doing about 13 of the damn practice tests, my scores varied over a pretty wide range (160-170). any test that yields such varying results seems to be a poor indicator to me. there's a big difference between that 160 and 170. i've noticed some other people having some wide-ranging scores. is this the norm for everyone or are there just a few of us freaks?
I had a large range, too, 163 - 174. But I also had the problem that I was never able to take a test in its entirety in one sitting because of my baby.
I generally did 2 sections at once, and would come back a half hour or hour later to finish the test. I did "feel the burn" (and then some) on LSAT day because of it... but as long as my score is not below my practice range, I guess I'll be okay with it (enough not to take that thing again, anyway).