I have never heard of LOI used in baseball recruiting circles....only NLI.
In the past, an NLI was only signed if the player was receiving some form of athletic grant in aid.
Under the new rules, the supposed standard is a minimum 25%.
However, I have seen some confusing posts. Apparently, the rule was amended that athletic AND academic money could be "blended" to reach the 25% minimum. But then there were some follow up posts stating the blending rule was only for schools who did not fully fund 11.7 baseball schollys.
Not saying this is 100% correct, but that is what I have read here, BA website and NCAA website.
FYI....I know of at least 3 kids in our area over the past 4 years who were announced in the media as "signing" with a certain school when in fact they were really walk ons who received academic money...... I know for a fact that some coaches tell kids "It doesn't matter where the funds come from.....if you want to tell people you got a scholly from our school tell them,,,,that's cool" (obviously a paraphrase)......