Whether they improved or not I would never in any way think of including them in my bet. Though, betting on them seems quite harmful to me because I almost got heart attack yesterday due to the way they were missed using their opportunities against Burley. Because had it been they utilize their opportunities very well yesterday, I think the game would have been an easy win for them. Even though this has master them in such a way that their winning normally happens by luck, which is very annoying because Man united is bigger than this.
A squad under development can have good improvement and starts to get better results but surely they won't be able to perform well and get good results too consistently. Inconsistency means it's very dangerous to bet on such squad's performances as their performances are quite unpredictable so are their match results.
An example in the last season is Chelsea that were under development and even they finished in top four, betting on Chelsea's matches last season is quite risky bet decision and this is even more risky to believe in Manchester United and bet on their matches. They are in a worse quality, performance and consistent situations than Chelsea.