First of all I'm not suggesting beginners fool around with mixes! Trainers fly just fine without! I'm thinking of specific airplanes where coupled rudder and aileron helps with adverse yaw in turns. These are NOT aerobatic or 3D airplanes. I said in my original post "Your Extra should not be an airplane which exhibits much adverse yaw". By coupling rudder and aileron, enough to help with adverse yaw, you have only decreased the amount the airplane can be cross controlled; however, you have not eliminated your ability to do so, or land and take off cross wind!

Fly a Cub, giant scale bipe or golden era general aviation airplane, or a WW1 airplane where coordinated turns really are necessary. The option of having a rudder aileron mix might be a nice feature, should a flier feel that's the way to go!

If your flying well enough that you are comfortable with an Extra, playing around with mixes will only help you fly better!

So, to say to forget the word "mix" I still say "Horse Pucky"!