This is good stuff.

As we all know stuff happens fast. But then again there may be times when situations "develop" more gradually and you begin to realize your in over your head. These can be critical times which DO NOT, I REPEAT, DO NOT call for immediate action. I can think of a number of situations, where someone would have been better off waiting until some else came through to guide them down, or park the boat and hike out if it was too dark, or sit in the boat all night if necessary (better and easier than clinging to a rock), or call for assistance or just plain chill out until they could regain their composure, strength or common sense. Anybody who has spent time on the rivers around here has got stories and some of those I'd rather just forget. But while situations can and often do happen quickly, more often they go from bad to worse, such as losing an oar or oarlock and not holding up or not being sure that all is clear and committing anyway. Many situations can be avoided out of sheer respect and awe of the rivers we float. A couple of additional warnings I'd offer to the many excellant points already made are:
1. STAY AWAY from sweepers; they are DEATH TRAPS!
2. Make sure your boat is anchored properly before leaving it. How times has a boat floated away when a guy steps out and the boat floats up and takes off without him realising it. People do not have to be in a boat for it to be flipped or lost.
3.Use extreme caution when WALKING a boat through riffles in low flows. Many bad things can happen when Capt is not on the oars.
4. By the way, low flows and floating summer rivers keep my hair standing on end, they should for you too.
5. And oh yes, did you ever know a sailor that didn't carry a knife?
6. Last but not least, in fact, come to think of it it is so basic I'm surprised it wasn't mentioned earlier and also that it only comes to me now, is Driftboating RULE 101: If have to hit a rock, hit it STRAIGHT ON! Avoid at all cost broadsiding obstructions. And even if it was mentioned before, it bears repeating again. Sideways is bad,bad,bad. Hey, with practice you can even piroet off the rocks you hit. Very Cool.

Be safe and live to float another day. Even if it is a replacement.