One problem about modeling inqs is that there's usually a new account attached to it. The account hurts less at 1 month, 3 months, 6 months, 12 - 18 - 24 months,as it turns into a positive tradeline.
What we need is an intrepid member with a boring, static history who will take a bullet for the team by app'ing and being declined, thus no new account. We could then monitor this person's scores to see if there's any fade. Of course, there is no such beast as this member, and even if there were, her/his scores would slowly climb anyway, as existing accounts aged. So we still wouldn't be able to separate the inq effect out!
I was quoting someone who knows on the 12 months and out thing.
* Credit is a wonderful servant, but a terrible master. * Who's the boss --you or your credit?
FICO's: EQ 781 - TU 793 - EX 779 (from PSECU) - Done credit hunting; having fun with credit gardening. - EQ 590 on 5/14/2007