I read your first msg and know exactly how you feel. My 3.10 ds digs his heels in for everything. It is hard work to go anywhere, with the exception of pre-school which he absolutely loves.
The dressing thing is our big battle too. He physically can do it, so I don't think I'm being unfair. I know he goes to the toilet by himself at pre-school, but each time we try to be tough it results in wet trousers... The Big boy stuff really doesn't work - we've had lots of talk about babies recently and not wanting to grow up - the two probably go together, but don't make it any easier.
Add into this a toddler going through the running off stage and screaming when going into his car seat (I know this will pass, but WHEN????) - there are days when it is too much hassle to do anything.
To be fair to DS1, he is shattered after pre-school. Also when he does get anywhere he always has a nice time. I'm always saying to the next mum, "Does he look like a little boy that didn't want to come?"
DS1 is 'naturally cautious' - sometimes frustratingly so - but I do get him to gym where the teachers get him to do loads that he would never do for me. He's also got a big smile which I think will get him through quite a lot in life.
On the plus side, I can't see too many trips to casualty with DS1 - I wish I could see the same for DS2!
Not sure any of this is any help - you made me feel a bit better anyway.