I had the opportunity to train with Dave here in my hometown. We did that Iron Cross both seated and standing - it was a dam good excercise.
Dave is known for agressive training, this was a really good excerise, BUT, you first should be familiar and practiced with weak hand shooting and crossovers and weak hand reloading before attempting this.
G19/G23 at all times.
"There are no advanced techniques, only advanced applications of the basics."
"Amateurs practice until they get it right, professionals practice until they can't get it wrong."