Nah the way I see it his strokes simply aren't suited to the style of play they are trying to force him into. A one handed backhand defender will get eaten alive nowadays (see Gasquet). Federer won so much in his career because defending and scrambling was not his main strategy, but it was what he wanted to do to his opponents. The reason RF lost so much to RN at RG is that he couldn't finish the point and Nadal gradually managed to push him behind the baseline, where Roger would lose the vast majority of points. Federer never wanted to get into that position, because he knew that it is a losing position for his style of play, yet Dimitrov seems to be looking to play from that position willingly.
It almost looks to me like Dimitrov is trying to play unlike RF because he hates the baby-Fed nickname so much, but I don't get it. He was playing better, more successful tennis when he played like that, even pushing the top guys. Nowadays he just loses to almost anybody out there.
In conclusion, you don't base your style of play on your physicality, but on your strokes.