It would be a weird fight. It wouldn't end in stoppage, it goes the distance. Johnson is more active, or at least used to be really active. This is a fight Abraham can actually lose, but if he wins it means nothing more than beating a 40 something year old game fighter who just retired and came back. He gains nothing but a name on his resume, not an impressive win at this stage. The fight would be more about how low can Abraham go, how limited is he. Is he so limited that he can't even beat this version of Johnson?
Abraham vs Green would be a much better fight. Although Johnson stopped Green, at least Green is young, just came off a TKO victory, is confident and he seems to send guys on to bigger fights. Like the watered down, less[way less] accomplished Zab Judah of 168.