Definitely a fair point, and i must admit I was more thinking about our best performing 11 rather than having the MK Dons game in particular in mind.
To answer your question, no, from what i've seen Mcglashan and Dickensen don't appear to be great defensively, but do we need them to be? If we have the back 4, with Hess and Loft box to box (Hess probably slightly behind) then you just have Mcglashan and Dickensen working hard back, it should give us enough behind the ball.
I'd hate to see us sit back in the MK Dons game waiting to be picked off, when we did that last season we were awful and a loss waiting to happen, hitting on the break is the way to do it with our pace in the team. Although having said all that, I wouldn't be surprised to see us play 1 up top and a traditional holding player (Morris maybe) in a protecting role.
Whatever happens i can't wait to be in MK for that first game! Got the tickets through yesterday and picked up my season ticket so can't wait for it to all start again.