Obviously it wouldn't need 20 minutes if you are stirring it, but I don't stir it as that would take all of the air out of the mixture.
I'm intrigued by your 20 minute recipe Fluffs! Do you eat it - or sole your shoes with it?
Eggs, milk, dash of salt. Whisk it in a bowl, pour it into a saucepan and put the lid on. Gas burner at lowest setting. Leave the mixture to cook, no stirring or folding or any other tampering that could cause the mixture to lose air.
Depending on the volume of liquid and the diameter of the pan the time will vary. For an omlette you would use a large diameter pan and a shallow depth of liquid, but for scrambled eggs it is a small diameter pan and thus a greater depth of liquid. I use a 16 cm pan and the uncooked liquid is usually about 1/3 of the depth. As it heats/cooks the air causes the mixture to rise but it can't escape because the surface has already firmed because the lid is on the pan.