My opinion is that in the example you provided, you don't say if the money is needed for cap purposes, assuming it isn't have given the receiving team a 5 million dollar advantage over all of the other teams, and have given yourself a 5 million dollar disadvantage for that season. 

So team A has an effective budget of 190 million, you have 180 and everyone else has 185.  Thats not a huge difference but can swing on signing, one player and can effect fair and equitable play.  Plus it never stops with one transaction, does it?