The question is what the two back scheme is meant to accomplish. I'll use a pitching reference, if you a fastball/slider guy and you have a 65 grade fastball and a 60 grade slider (both above average), why would use a 40 grade (below average) change-up?
Wrinkles for most offensive schemes are best when they are used sparingly. The more you allow teams to load up in the box for Cliff, I'm not sure that he is going to be as effective. Two back systems where Cliff is under center, isn't necessarily an awful idea, but how deep and wide is it to get the most out of Eli, Xavier, and Joey as well as Cliff. If really it is the Cliff and Eli show and Xavier or Janacaro (if he were healthy) are decoys, what is the benefit of running out a formation that actually makes it more difficult for the offense to execute.
The more that teams are allowed to key on Cliff as a run-only guy, the more it requires a lot more preparation and depth of knowledge for offensive personnel to be successful every time they run on the 20 or 30 personnel. A good example of it was the power formation Bobby used with Eastwood on the goal line, and similarly the formation that stitt used to get the ball in to the endzone against NDSU.
Variance is important, wrinkles are a great thing to have in your scheme, but if it is really your 3rd best schematic option you have in your playbook, you are better not using too much because you'll get exposed eventually.