Have eaten in the dining room on several occassions but just dined at the bar for the first time and it was completely enjoyable. Not only can you get the feasts available in the dining room (5,8, or 12 course) but you can get a relative bargain meal of 3 courses for $58 (we opted for the 3). The really nice thing is you get all whole parade of amuses like you get in the dining room (maybe a little less but it didn't seem so) even when doing just the 3 courses. Also, I would never even think of dining in the main room without jacket and tie (maybe that's just me) but I was completely comfortable with jeans and a button up in the bar. Cold night, nice fire, great food, now that's a nice evening. The bar is also a great place to drop by and get a fantastic cocktail, glass of wine, or beer.
And FYI - the egg dish, the gnocchi dish, and the duck dish were exceptional.