First of all, congratulations; the XT double is a great ski-fast enough, and quite stable in big water. I've had both the fg and now, the carbon layup. I've also owned the Elite Double, another outstanding boat.
If you've not paddled doubles before, the initial attempts might have you and your partner experiencing a case of the wobbles. This likely stems from staying tense in the boat. As with all skis, it's about bucket time, and acclimating to the paddle stroke and reactions of your doubles partner. Give it time, and be sure that you're strokes are synchronized.
Something else to try is that you have proper adjustment of the footplates to enable you to drive against it. The XT has very flexible plastic footplates in the rear stoker's footwells. It's easy with leg drive to flex them forward, lacking a solid rear platform. I've blocked mine out with construction styrofoam for my usual tandem partner. The Elite has rigid carbon footplates front and rear.
As to the draining, try epoxying venturi bullets on. It does help especially at slower speeds, but I've found the drain speed to be lacking as well. The good news is, the high side rails make for a dry ride to begin with.
One last mod you might make is to swap out the shark fin rudder for a squarer-edged version. Enjoy the boat!
"Nice? It's the only thing," said the Water Rat, solemnly, as he leaned forward for his stroke. "Believe me, my young friend, there is nothing -- absolutely nothing -- half so much worth doing as simply messing about in boats."
'The Wind in the Willows'~Kenneth Grahame
