The only reason that there is the common miss conception that it does not pay to put both feet on the deck is because none of you have good enough balance to get it right. in a blow i can get my crew standing with HIS front foot on the corner casting.
Surely anyone has the common sense to work out that the further back you are, the more anti-pitchpole moment you have, its basic physics, it just requires the skills to keep your feet out the water.
Also, if you can both be supported on the wire, then go for it as you will obviously have more power in the boat and more speed, despite your corse (broard reach, beat, whatever!) This was proved sailing in after trainning in Austria, yes some pitchpole but if you don't find out how far you can push the boat you will either over or under push it in a race