As an avowed carnivore, I sometimes get the veg tasting menu at very good restaurants (CityZen! Go! Now!). It takes more skill to compose a very good vegetarian dish because a chef doesn't have the central focus and dominant flavor of the meat to fall back on - it's a chance to showcase a great chef's skills (and Patrick O'Connell certainly qualifies as a great chef). In fact, L'Arpege, one of the best reataurants in the world, went ALL vegetarian a few years ago(they have since reintroduced seafood and poultry).
You can be sure TIALW won't be giving you collection of side dishes already on the menu, or boring pasta with tomato sauce. I wouldn't have any hesitation at all.