I am almost done potty training my 22 month old daughter----controversially young, i know; but she displayed all the readiness signs AND has been 90% BM trained for almost a year(that's another story). anyhow, mine would also wake up dry but whine and carry on when i told her it was time to sit on the potty.
i did not make it an option, even resorting to a swat if she refused to sit, or whined about it. i would say, "you just have to sit on the potty. after you are done, it will be my turn" i emphasized that she had to sit calmly on the pot when i said, but that she did not have to go. peeing was her choice, sitting obediently was not. then we made it fun: bubbles, special toys, games, songs with motions, showing the baby ("look, Sissy, what Momo can do!"),moving the potty to the coffee table for a special activity. i also used a timer with a pleasant ding, and of course i could set it for 5 seconds if i wanted, and she felt less that mom was controlling the situation; it was the universe giving her a sign or something. (i use it for cooking, too, and she still runs for the pot when it goes off! ;-)).
she figured out quickly that it wasn't worth it to fight sitting on the toilet, and it was actually a pretty good deal to sit there. peeing followed, and then one great day when she held it and said "potty, mama!" and we were on the homestretch. hope all that helps a little. good luck!