I work eddies upstream and ride current downstream. On a full day paddle I will usually stop for lunch, but thats often just two Clif bars and something to drink, and not more than 30 minutes. On the shorter paddles, I usually do not stop. I will stop paddling long enough to eat something usually once an hour, but thats just long enough to put food into my mouth. I actually enjoy grinding away like that more than recreational "sightseeing" type paddling.
Might just be weird