Thanks for the explanation - I wasn't sure about how it worked when I first read your post but played around with it at training tonight and i think I get what you mean.

I was taught to step to the left with the jab by a coach who didn't believe in pivoting with the right cross - I was never taught that again so I kinda guessed that was just to allow the right to be thrown without a pivot.

......... I might quiz you about it in more detail after I've tested it in sparring though to make sure i understand you!