Can you walk from...
the Boston Convention Center to Barbara Lynch's new spot, Drink, or is that a bad idea?
Easily, as long as you're talking about the convention center on the waterfront, not in Back Bay.
From the BCEC walk down Summer St toward downtown. In about 1/4 mile you will come to a bridge crossing over A Street. There will be a staircase on the bridge leading down to A street. At the bottom of the staircase go straight about 50 feet to Congress St.. Drink is directly across the street on Congress. FYI Lucky's is also at that corner but not in the same class.