Maybe. Reportedly he wanted to switch to a 433 as main formation which would likely have given what he wanted - more control and less chaotic games. As mentioned before here that would have required proper CMs, instead Ronaldo came in. Who can work great in a 433, but if signing him means there is no money left to fix the midfield you will fail.
Considering that McKenna and Carrick seem to do well I don't think that the actual training was that bad (but I also don't think it was excellent), so probably the coaching setup was at least acceptable.
I think his biggest failure was that he had an idea but just failed to identify the right players, and that's something a good DOF and scouting department could definitely have helped him. Ronaldo was an issue, the Sancho saga was weird, such things should have been prevented.