It should. Here's how it can help you: * You play the openings you usually play. This will allow you to get more familiar with the move order, opening nuances, and the resulting positions. * You still try to make good chess moves. read more
Playing blitz makes you a stronger blitz player. It has little effect on your classical skill. At best, you'll learn to recognise some tactical shots instantly, but at worst, you'll make moves without thinking sufficiently deeply. These effects balance out each other, I think. read more