We don't know the full facts - and never will. Neither do we have the interpretation of all parties to review. Such a forum post makes one suspicious of long standing simmering resentment between the airfield users.
Any sensible instructor receiving a call from a Pitts to jump ahead at the intersection so allowing the student to back track line up and collect their thoughts for a few minutes, without delaying others, would be delighted to say yes. Why would you want a faster aircraft, with bugger all field of view, coming after you wondering where the hell you are? To respond negatively to such a call or be irritated not to have received one is irrational and peevish.
Students are taught the importance of human factors. Being unable to cope with an immediate, perceived, act of injustice perpetrated against one can lead to aberrant behaviour eg road rage. In this situation should the instructor have taxied back, lodged his complaint with the CFI, calmed down over a cup of tea rather than taking of in a red mist is open for debate.
Training is the lifeblood for many clubs, but this does not give instructors irrational rights of claim to real estate both on the ground and in the circuit - it's always a balance.