So i was thinking. Does the way you attach a muzzle device effect accuracy?
Yes.
and, no, sort of...
Attaching ANYTHING to your rifle barrel affects the way it shoots. That is the "yes" part. Flash suppressor, "silencer", muzzle brake, BAYONET, or even the tube magazine support bracket, ANYTHING you attach to the barrel changes it's vibration when fired and can affect accuracy.
The difference between a bare barrel and one with attachments might be small or it might be huge, that is something only testing of individual combinations can determine.
HOW you attach the device might have an effect on the amount or consistency of the change, but not on the fact that there is a change. That's the "no...sort of" part.