Is that really down to the fact they've had a gazillion managers or more down to the fact that they've spent gazjillionmajillion pounds on players?
What kenwright brings to the table is stability. We've had the same manager for longer than 99% of clubs and he gets to do things his way which allows us to over perform compared to our fiances.
What roman brings to the table is lots and lots of cash. He sacks managers like it's going out fashion and sabotages his own team by interfering but he pays the bills.
Ultimately the latter approach has won them 14 more trophies then our approach has won us. What kenwright brings to the table that a roman doesn't has proved itself to be meaningless.