Well, I don't agree.
Motivation for this permanent tanking is the associations (platinum rewards, no motivation for the other competitions and the top100 list).
With this implement, a group can have 2 weak teams, which every season will loose -1* and after some seasons they will be -5* or -10*.
Those fake accounts with the other strong group mates will make a very low avg q group which will face weak opponents in every asso draw.
Remember, tanking is the way, not the motive.