2012 Season so far raising a question

Firstly, I'll start it off by congratulating Lewis Hamilton on finally achieving his first 2012 win, may a few more come swiftly, great race to watch and very on-edge stuff from the front runners. Really didn't see the last few laps with Grosjean and Perez coming, at all! Was nasty to see Button struggling for pace, but a bit lightening to see Massa starting to pull a bit of pace earlier on, I dont know where his career may end up at the moment.

But Canadian GP aside, this post is about how the season so far has started to raise eyebrows for me in the McLaren garage, weekend after weekend, the mechanics are having issues changing wheels, how hard can it be to put a wheel on properly when you practice so much over the close season and every other weekend? Could anyone elaborate on the answer Im going to give other than "the Mclaren mechanics are W4NK!" ?