Nobu

• Tips split between army of waiters (you're never served by just one person), maitre d', kitchen staff, bar staff: basically everyone except management. Waitresses reluctant to confirm this, but manager will*.
• DO: Go with someone who's picking up the tab (it ain't cheap), order the bento box and the papaya & carrot juice - it's £6.50, but it's yum!
• DON'T: Pay the discretionary service charge of 15% on your card; better to leave a cash tip. The more senior the waiter, the more of a share of the tip he/she gets.

*there are philosophical arguments as to whether your "tip" should go to kitchen staff, bartenders and the like. Why should the waiter be the only one to receive a gratuity? If so, pay the service charge at Nobu with a clear conscience. If not, then you may have to go somewhere else.