Actually, Dan, it doesn't matter a fig what you 'break' from - finger, echelon, box, diamond or whatever, as long as it is briefed, understood and properly flown.. The leader CANNOT always be in view of the wingmen, as once he/she 'breaks' then it is up to the next a/c to locate the lead after the break and position accordingly. A vic break leaves 2 and 3 'formating' on each other for a short while and then 3 needs to locate 2 after his break, and avoid (both!) as he did.
I suspect cessnapete in post #78 on the mil forum thread has given us the clue to what triggered the collision. I also read 'suggestions' that not everyone attended all the briefings.
Let's just be thankful that the P51 guy got out and the Skyraider survived too. That latest video shows just how late it was.