It won't help your credit but it won't hurt it either. You're thinking of the $2 trick which is a totally different animal.
They charge interest on the entire statement balance if it isn't paid in full, not just the amount left unpaid.
1- Thanks. I'm definitely not getting mixed up with that. I was told this about interest, I just don't remember if it was from someone reliable or someone guessing.
2- I hear, but it's interesting because my statement closed with a balance of over $400.