A coupple of issues in this thread! (Way to multi-task here people!)
Treats: the whole "upset tummy" is definately a too much of a good thing issue. Whatever you decide to treat with, make them very small and just watch how much you give. My dogs go nuts for bologna or plain ham. Cheese is the perenial favorite, but never underestimate the power of a "Good Boy!!"
Coats & "Cold" Weather: My boys have it rough. Living in the Midwest, it is not uncomming to spend all witner in the single digits (not counting windchill which often kicks us into the negative teens, if not worse). Both boys have dog coats made by Lands End in the same style (and cold weather specifications) as their Squall jacket series. It consists of an easy belly band and front chest closure meathod. No worries about tails or legs. Easy on, easy off. And my boys live in them during the winter. Dogs, just like people, quickly acclimate to the weather. If we deicde it's "Cold" at 50 degrees, they start to feel that way. If we decide 50 is downright balmy, the dogs learn that too.
Walking: Oh, the perenial issue of B's! I agree with many of the posters here: it's all in the tone and your attitude. If you decide to be upbeat and positive and decisive, the B will follow! (But probably will quit at mile 6 if he hasn't had his ice cream yet… grin)