This is actually part of the reason I prefer to hunt by myself sometimes. Commands are noise, and pheasants hear noise. When its just me and my dog, we make no noise. She knows what to do.
A couple weeks ago I took a friend (no dog) with and told him ahead of time that we weren't going to make any noise. Normally we yell "hen!" if a hen gets up but I told him not to do that anymore because the last time we yelled hen, the roosters were getting up wild out of range. Noise is the enemy this time of year.