We had several discussion in the previous threads about the MOU, and essentially the deal is:
In general, an MOU is like a "pre-contract". In some cases it is binding, but not in all cases. In any case, it lays out the basic terms of an agreement and forms the basis for the final contract.
In coaching, this last point is important, because contracts (especially for state schools) take a LONG time to draft and finalize. Usually way longer than a school can wait for a coach to start work.
The status quo is that an MOU is drafted and signed and a coach can get into the HR system and start getting paid and accessing facilities, etc. There is a lot of trust attached to the MOU in these cases.
Dooley worked under an MOU for 3 months. Mike Price only ever had an MOU at Alabama and was fired with nothing but an MOU in place.
Every coach out there coaches under an MOU at some point. The hiring process in coaching depends on it.