I have done a direct grill Butterfly Leg of lamb for years to rave reviews that sounds similar to Cathy's.
We call it Madame Butterfly LOL,
and marinate it for a while (whatever works)
in orange juice and zest
sherry, soy sauce , garlic, ginger, and maybe some other stuff (I don't have the recipe in fromt of me.)
I grill it over medium coals/fire for 10-15 min/side to medium/med rare
it gets crispy bits carmelization, and it juicy inside.
The flavor is so wonderful. It's a crowd pleaser, and non-lamb lover converter.
Haven't tried one in the smoker yet, but what could be bad?
"If you reject the food, ignore the customs, fear the religion and avoid the people, you might better stay home."
~James Michener