As a T5 student at a T2 school that did not apply to any T14 schools, but with an LSAT high enough, and a decent T2 scholarship, I would like to confirm a couple things the OP said:
If you can score T14 numbers on the LSAT you can almost certainly rank in the top T10 (T5%) of a T2 school. It's not about one exam going bad as some others have tried to say, but rather the top few students at my school are separated by a pretty hefty GPA margin from the T10% line (about 5x the T10%-T15% margin). Just saying, it's probably true that you can at least score in the T5%/T10. This will get you a grade-on onto LR, also, so even if you don't do well on the write-on you'll get LR.
That said, while all of the T5 and probably even T10 got 2L SA jobs, to say that all of the T10% got jobs would be very wrong. There are quite a few T10% students without them, but then again there are also also some T20% with them. Point is, your odds start going down drastically after the T10 line if you are not a top notch interviewer (I am certainly not). As a T5 student, I ended up only with a couple callbacks and really only one good offer for a 2L SA position, and I am on LR/etc.
However, it is nice to be working shoulder to shoulder 2L summer with someone who went to Harvard and easily has 5x my debtload (I will have only paid about $30k in tuition total throughout my 3 years). But, if you flunk out of the 15 or so OCI firms, you may be screwed. Firms outside of the geographic area really do not want to talk to you, either. People that flunked out in 2L OCI are also pretty much SOL for any kind of paid summer employment, too, biglaw or not.
Also, I will say that it is kind of crappy going to a school where the vast majority of students will not have a biglaw job. You feel like a dick talking about your summer job, and morale in general is pretty low. Also, career services/professors/seminars/etc basically assume that the people in attendance will not be working biglaw. Just saying, it would be nice to socialize with others that are getting the same type of employment I am. None of the good friends that I have made got onto LR, and none have biglaw jobs.