Also, I think a lot of us are putting too much "weight" (pun intended) on his lack of bulk vis-a-vis his longterm potential as a high-major talent and as an effective post player. Basically, I think we're conflating the fact that we currently feature post players who are very skinny with the fact that they are simultaneously, well, not ideal rebounders or defenders. The weight issue isn't helping, but it's not necessarily the cause. Most high school post players (and basketball players generally) are pretty skinny. The fact that our skinny post players are shitty rebounders, defenders, and post scorers has a lot more to do with their mental temperament and other intangible factors than sheer lack of bulk, IMHO.
Basically, I don't think the lack of weight on Washington (or Rountree) should be cause for concern on its face. If they end up ineffective as high-major frontcourt players, chances are that above-the-shoulders limitations will play as much of, it not a larger role than the lack of a few extra pounds.