T.G.
Heh. Oh my goodness, yes. All three of my girls started this kind of thing, right around that same age - my five year old will STILL occasionally try it on for size.
I usually used "silly" to snap them out of it. Something like this:
"OK, honey, time to put on your shirt."
"I can't, it's too hard!"
"Too hard? To put on your shirt? You must be doing it wrong. First, sit down like this and put your feet into the armholes..."
At various times, I had socks on my hands, pants over my head and stuffed animals down my blouse - but usually they'd "straighten me out" pretty quickly.
I think the hardest thing is to keep your cool when you've got 38 seconds until that last train is pulling out of the station and Little Ms. Thing is standing there saying it's "too hard" to put on her shoes. ARGH! It's VELCRO, don't give me that 'hard' crud! Why, when I was your age, I had to use laces! Which I had to make myself, every morning, from wheat stalks I had picked the night before and cured in the oven overnight...! I always found that trying to get out the door ten minutes before I actually "had" to get out the door gave me just enough time for one last battle without losing my temper.
Hang in there - these phases come and go. The less it bothers you, honestly, the sooner it seems to go.