Slide Canceling

Mega Man cannot jump out of a slide in Mega Man 6. Whether underwater or not. 
 Pressing A again in a slide will make Mega Man stand up. This leads to two ways to cancel your slides. 
 
 "Back cancel", by "pushing left" (assuming you are sliding right) 
 "A-Cancel", by pushing A 
 
 This behavior makes the game require fancy finger gymnastic to perform quick slides and jumps, such as the "Clutch Jumps" in Wind Man's stage. 
 It also makes identifying platforms where a single full slide can be made extra important. Several such "Raiden" slides are noted in guides.