I wouldn't blow someone off just because of a miserly deadline.
I'd probably discuss it with the client first and work something out, or try to.
But about deadlines themselves, I have a really hard time NOT making them.
If I ever missed a deadline I would be so ridden with guilt! It's just not something I could accept in my own working ethics.
If anything, I submit my work a little earlier if possible, without squelching quality of course, just to be safe!
To me, deadlines are like important appointments: if you agreed to it in the first place it seems rude not to hold up your end of it.
Even more so if you're not a newbie, cos you should know better!
Just my take though.
