I think the skills used by lawyers are very different than those used in yeshiva. In yeshiva, there is also a large element of understanding lomdus which is not relevant for law, and of reading and understanding gemara and rishonim which has no corollary in law where the stuff is written in english and in a way intended to be clear and concise.
Also, I do not believe the LSAT can be studied in the way you suggest. I do think it is an intelligence test.