United under Wilder have shown before that they put a huge amount of value in very small sample sizes - Brewster, Cannon, not changing the approach at all after 19/20. All 3 of those things were decisions made on outlier performances, unlikely to be repeated. But United acted as if that was a guaranteed return. The goals against with Souttar in the team was unsustainable and I think United will likely concede 40+ this season even if he signs and plays every match. Doesn't make Souttar a bad player, he's very good. But outcomes like conceding 11 in 23 are very, very, very rare
I also think we are vastly underestimating how much attention Hamer drew from opposition teams, and how much Brooks started to draw towards the end of last season.
Donavan may well be a good signing but he'd have a much better chance of showing it with an opposition team having shaded their defence towards Hamer. Now, teams will start off defending straight up as I'm not sure there's really anyone in the squad who'd warrant that extra planning