I agree with Bertie Thruster
Just look out the window and fly the thing, I remember I used to worry about all these things, I had sooo much weird information in my head it always made flying more difficult for me. I was always thinking of werid effects and aerodynamics.
Then I stopped worrying about all this stuff, went out and strapped a helicopter onto my back, and starting that moment I felt more comfortable than ever flying a helicopter.
There are some helicopters with nasty habits that require some thinking on the pilots part to find out what's causing this erratic behavior and try to deal with this as you are flying, but if it doesn't well thats less thing to worry about.