The problem is working out who was behind the signings in the Howe era. Hughes and Blake wanted more power and to be in control of the signings and have a manager as a coach and have achieved that model post Eddie. Pre Eddie it’s a little more confusing
I’m sure they had some involvement but for example we know that we signed King because Eddie watched him at Utd reserves when at Burnley, Stanislas and Gradel he’d managed before, Defoe he’d played with, Ake he said he’d signed because of his performances against us and I’d have thought Distin and Murray weren’t scouted.
We know Hughes found Iturbe as he spoke about it and can assume he probably found Lerma, Mousset and Rico.
Basically prior to Parker I’m not sure how you’d be able to measure this.