Our latest trainer instructed us to muzzle and alpha roll our dog twice a day as a dominance exercise. Should we stop doing this?

We have a dominant/agressive 16 month female doberman. We have purchased and implimented all of your training videos and hired several local trainers. The latest trainer, has instructed us to do an alpha roll with a muzzle 2 times a day as an excercise not as a correction. Our doberman growls and freaks out when we do this but eventually calms down. We are rolling her on her side only not on her back. Should we stop doing this? I know your other articles are adamant about not using alpha rolls for correction but what about as a domninance excercise? I would appreciate your advice.