not me but the guys at megauirs said it. went to one of their detailing days.
am intrgued though, only difference between soft and hard waxes is how they are stored as far as i'm aware. wax is wax? is it not? yes there are variations in ingredients, but is it not to do with the delivery of the wax dictates the consistency? i.e. those who want to put it on by hand and those who prefer a machine application?
i'm no detailer, so interested to learn more. as far as i was aware you can;t layer wax, you can just go back over and make sure you did the job properly a 2nd time round i suppose. (completely top up the pores in the paint.)
as paint is just like skin, it has pores, it breaths, dirt gets trapped in the pores etc hence the need for clay bars etc