I never heard about that custom. In fact, I've seen job applications that request that you share your LSAT score. I think it was the Office of Chief Counsel at the IRS that wants it. It makes sense to ask for it, too, because it's a useful reading comprehension test.
At best, it's a waste of space. At worst, it triggers social sanctions (like I said, tossed in the trash), and indicates unpleasant personality qualities.
I dunno, I personally consider it to be a valuable data point. Some older attorneys I know also do. It only makes sense to put it on the resume to differentiate yourself, and I think I'll take the risk. If there's some "custom" that it doesn't belong on the resume, now's a good time to start putting an end to it.
I don't have an endowed merit scholarship. The reason I'm going to the school I'm going to is likely clear: I didn't do as well as I could have at college. It's not like they'll think, oh my god, this guy's a murderer, and the Harvard admissions committee found out and decided to reject him.
You quoted some text I typed out and implied that it suggests I have serious problems, but you didn't say why.
On the guarantee: what happened?