This was posted in road, but to no avail.
Sprinting, or general power out of saddle, comes in two forms to me and the riders I casually associate with.
Stiff sprint - No 'wobble' in the bars, mostly bicep power pulling up on the hoods/drops.
Swerve sprint - Pronounced wobble in the bars, and amplified 'sway' of the frame due to this. Pressure more even, if not pushing slightly down on the hoods/drops.
Any insight into WHY we do this, when to do this, and to what end these means come to, would substantially help my form at this point.