For Poch this is true, to date his best signings are the ones that didnt cost much other than Sanchez. This is why you cant really make the argument if Poch had the cash Pep did he'd do amazing and walk the league etc You actually have to have the ability to spend the money well and manage big money signings. It could just be that Poch is better at harnessing lesser known talents and developing them which is why we are a perfect match for him....
I think if Poch was allowed/able to sign his first choice target in every position required then you'd see a better success rate