2013dad,
In trying to envision what you are saying, it seems that there are two aspects to the "commitment." The first is your son can change his mind.
Implicit in that is the concept that after he makes his commitment, he will continue to look and talk with other programs. If he tells other programs he has committed, most will honor that. Not all, but most.
Are you saying that your son is okay to commit, okay to continue to look after he gives his word, okay to change his mind for a "better" perceived opportunity, okay to then decommit, and they okay to verbal again, all in the name of baseball?
My view/response is if all of that is roughly correct, there cannot be any complaints if, at the end of the first year, or before, if the coaching staff were to leave before your son steps into the classroom, there is a change of view from the coaches and they either don't ask him back or move to another player.
Personally, I think swampboy has provided a wonderful assessment of this entire situation.
We can rationalize this in many ways.
Integrity of our word is what our son's and we as parents bring to the process.