I expected you to be quicker off the mark on this thread A and C.
Since you have lost a friend, it is perhaps to be expected that you will take an emotive view of discussions on this topic, which seem to crop up periodically.
So I will forgive the "yak flying scum"
slur even if others may not; even if your comment is incredibly insulting both to the memory of a deceased friend / family member and to a group of pilots who, collectively and individually, rate as one the most talented that I have seen flying in the General Aviation scene and who have entertained hundreds of thousands of people throughout Europe at a variety of airshows; and even if your reaction is just completely out of proportion to the occurence that propmpted the initial post ie that Stratton feels aggrieved because someone did not respond to him in a manner that he would have preferred.
Stratton - if I had a dollar for every time a complete stranger did not react to a greeting or question in the way I would have liked, operating my aircraft (yes, it is a Yak) would be a whole lot cheaper. Perhaps you might like to consider that formation aerobatics is a discipline that requires concentration and, just as you may not appreciate interruptions from strangers during a walk around, perhaps you were asking questions or issuing greetings at an inappropriate time - I don't know - there could be a 1000 completely innocent reasons whay you did not elicit the response you were hoping for, and not all of those reasons are due to the person of whom you were asking the question.
However, your assertion that the formation team operates with a "lack of regard for the safety of other users" is just wrong. If you are nervous of taking to the air when formating aircraft are in the vicinity, fine. But use of Mark One Eyeball, listening out, communicating clearly with the Air/Ground and if in doubt, asking what is happening will, as in most flying situations, help you to fly safely. I think you will find the team doing likewise.