I feel like this isn't true. Hardways are a perfect example of this. You can approach with a rail heelside and hardway into a slide. That'll leave you with a frontside whatever. Lip, blunt, or board.
Am I wrong? I dunno I never really examine my tricks. I just do them.
Hardway just refers to the direction you rotate onto the rail, being that your spinning away from the rail. The rest still applies, so if you wanna get technical...
Say you do a Front Board, you could also do a 270 Front Board or you could do a Hardway 270 Front Board.