You're right it was frightening.
I've read several times in these books and from other players quotes how for example John Harris used to send the players out with the tactics, "get stuck into them lads" and then the senior players basically tried to work it out for themselves. When Sirrel was manager he would bore them rigid with endless practice matches which only served to knacker them out. Haslam, apparently, would not be seen from one match day to the next leaving Bergara to coach the players (incidentally Keith said that Bergara was the best coach he ever had and everything before that he'd learnt from his Dad!).
I suppose I'm assuming that while this was going on at United, Shankly, Revie, Clough, Bobby Robson and maybe others were probably a bit more progressive in their thinking. I just think that given the players we've had, if we'd just had someone in the background with better knowledge or understanding, we may have had more success.