Altered ingredient amounts.
This was GREAT! I made it for company tonight (which always makes me a little nervous, trying a new recipe with company coming) but it turned out exactly as I was hoping. The only change I made was to use half soy sauce and half teriyaki sauce instead of all the soy sauce that was called for. It was sweet but not too sweet, and the meat was so moist! It tasted like I had marinated it. I did only end up cooking it for about 40 minutes and it was completely done, even a little more dry than I would have preferred.