“Feuding between Trump and Cruz is extremely counter-productive”
No, it isn’t.
Trump and Cruz are dividing the anti establishment vote.
After Rubio, Kasich and Christie drop out, Jeb will be competitive. Cruz will have to drop out or Jeb might get the nomination.
That is my point, let the establishment candidates spend their capital attacking the insurgent candidates and each other. The insurgents shouldn’t attack each other; it will just create hard feelings between the Trump and Cruz supporters and help one of the establishment candidates eventually prevail.