As an organization? Yes I can blame them.  They picked a project QB in the 4th round last year without seeing it through and ended up picking another QB in the draft and in free agency this year.  Turning a 4th rounder into a conditional 7th is a bad return on investment.  Now the current coaching staff and GM may not have liked Cardale (which is pretty obvious), but again nothing like selling when the market is down.  The Bills could have easily waited a little while to see if teams had a major injury and maybe let Cardale have an opportunity for a decent preseason showing and turned that into better trade value. 
  
Look this organization doesn't get the benefit of the doubt until they start making smart moves on the regular, regardless if a new sheriff is in town.  Different doesn't mean better, until it proves otherwise. 
  
I have no idea if Cardale will be a decent QB - he looks like he has some physical skills and some leadership ability, but he also has some really big places to improve his game.  With a project QB, it just seems very shortsighted to trade him when his value is low.