Choosing a winger over an actual LB to play LB isn't the best way to demonstrate Jose playing concervetly in a big game
Young is a defensive player. He is an average winger and LB. People's perception on what a full back is has been lost at Utd. If you think Young-Valencia are world class I think you should look at what the top sides in the rest of Europe have. Top full backs gets assists regularly vs the best opposition. Ours get exposed and found out vs the best in the PL but are a solid 7/10 vs the rest.
Most top sides have world class full backs which is why they all cost 50+ these days. Mourinho will always go to Ashley Young because he is won't go marauding forward like Shaw. Young who prefers to stay in his half and pass backwards and sideways.
Young and Valencia are diligent and robust. They'll do a job and get solid 7 most games but will always get found out vs top sides.
I know someone will come @ me and say 'Young and Valencia have been our best players this season' In a team with Pogba, Martial, Lukaku, Mata, Matic, Sanchez etc.
The fact that Young and Valencia are our best players is part of the problem. Mourinho doesn't know how to get a tune of out the adventurous footballers he has got and brought to the club. There is a lot of talent at the club but he doesn't know how to maximise its potential, at least not yet. He needs to find a system and shape that compliments everyone not just a few.
If he adapts we might see some more fluidity in our football. At the moment it's all very individualistic, we rely on a bit of brilliance from one player. I don't see any cohesion from defence to midfield to attack. We have no relationships between full back and winger. Our striker is very isolated. I think these are all valued questions to be asking in what is Mourinho's so called 'best season'. I think 2nd place is still attainable but we need to get our act together fast with Spurs and LFC flying and CFC finding a bit of form with Hazard.