They're letting themselves down, but the ball is in the wrong part of the pitch for them to get involved. We're starting attacks with Gareth Barry going sideways on the halfway line, instead of from the feet of Lukaku 20 yards further up.
With the attack (for what it is) coming from deep, all Barkley/Naismith can do is aimlessly drift left or right and are man marked by the defensive midfielders whilst the centre half picks up Lukaku, all at a slow tempo, so they are out of the game.
The wingers, on the other hand, have to attach to the full back, as there's no situation where our full backs can get high enough beyond to double up and cause the danger that way, meaning Mirallas can come inside and worry the centre halves, freeing up space for Lukaku.
So, in short, it all comes from Lukaku's movement - it may seem unfair that I'm picking on him, but he's the focal point of the whole system, and if what he's doing doesn't work, pretty much nothing does, as there are no easy options ahead of the play for the pass.
That's why we need to hit Lukaku early when confidence is low and see what sticks, then play off that. It isn't the philosophy of Martinez, but what it does is get people going direct and playing with pace, rather than overthinking.
