Recently while kayaking in a 3 to 5 mile an hour river flow I ended up broadside on a tree (playing with my GPS and not paying attention) anyway I rolled up the tree and my kayak took on water. I grabbed onto the branch that I was perched on and tried to right myself before I took on too much water. It didn’t work and my dad (also a kayaker) had to wade into the 48 degree water and pull me and my kayak out. When we got to the take out and I told my story to another kayaker he said I shouldn’t have grabbed the branch. Why not?
Not Envisioning The Scenario Well
but generally the thought is to lean into an object and push and move your self around it. When leaning against, the upstream edge of your kayak will go up, allowing the water to flow underneath. If you grab a horizontal branch and not lean into it, the water will push your kayak and maybe your body past the branch. In this case you end up fighting the current that is pushing the kayak downstream. At some point your strength will give out and you will be swept under. If there are other branches underneath, you may well up in a strainer that traps and drowns you.
If you encounter a rock, again you lean into (downstream) and push yourself around it. If you lean upstream, the upstream edge of the kayak may catch the current and flip you. It's possible for the force of the current to then pin you and the boat against the rock. It's harder for you to get out of that situation because your body is not facing the rock that you're pinned against. If you flip while leaning into a rock, at least your body is right against it. It's possible for you then to push yourself away from it and hopefully have the current help move you around it and freeing you from a pin.
Lean your boat! keep yourself over the CG.