A few friends switch to bidets a while ago and wont look back. Personally I just jump in the shower if it's that bad.
Try cleaning your hands with paper instead of water some day, and see how that works out for you. It's the same thing.
I'm sure you've had brown streaks inside the bowl that could not be removed in N flushes, but a simple toilet brush made quick work of the matter.
To use your handwashing analogy, try removing crisco, or some other substance that adheres to your hands with a stream of water. Now try physically wiping it with a paper towel. The towel will win every time.
This is to say nothing of the fact that it's quite nice to leave the bathroom with dry hindquarters rather than a bad case of SA.
You've obviously never used a proper washlet.
Crack hair is useful for a lot of things, keeping skin from rubbing, fart silencing, sweat management, etc. But you only need a bit of hair for that to work. 80% of the length can be removed with no ill effect, but dramatic improvement in general cleanliness and comfort.