roasting lamb

I had a partial success, partial failure, with l lamb roasting experiment last night. I started with a 3.5 pound leg of lamb (minus the shoulder, which is the way my market cuts it) and cut out the bone. This produced two separate pieces. Truth be told, I have no idea how to debone a lamb leg. I did my best to locate and sever tendons, and lay it flat. I then rubbed an herb mixture onto the meat--parsley, garlic, rosemary, ginger (all fresh, proportions ala Julia Child). I then rolled it, bound it with butcher's string and stuck it in the fridge for a couple of hours.

That night, I salted and peppered the meat and rubbed it in olive oil. It went on the grill at direct heat, 450, for about ten minutes (flipping once), and then I roasted at indirect heat, 350, for another 30 minutes before checking the temperature. This turned out to be overdone. And the crust to the meat was, frankly, too much for a roast.

It was a disappointment, of course, especially since it was the centerpiece of a four course celebratory meal. But I think in the future I can treat this much the same way I would a hanger steak. Cut the searing to two minutes a side, put it on indirect for fifteen minutes at 300-350 and check the temp. The searing should only serve to squeeze the meat to savor its juices. I am wondering here if it is not possible to slow roast it after a quick sear at an even lower temp (say, 250). I don't know enough about the mechanics of roasting to answer this definitively. Given that the lamb roast is so small (no six pound shoulder this), I ought to be able to treat it differently.