Like I was saying before, pollinating plants doesn't affect the overall potency, because only the calyxes that receive pollen will be affected. And even then the area around the calyx will still produce plenty resin (aka potency), only if pollinated it will also have to spend resources on growing the seed inside it's calyx.
Whatever calyxes you pollinate will produce seeds if the pollen is viable. If you do it very carefully, you can easily do just select branches and keep the rest sinsemilla. If you do it sloppily, you'll end up with a lot more random seeds in a lot more places. It's all dependent upon you and the way that you pollinate the plants as that's what will determine how many seeds you get and where they are located on the plants.