City firms are notorious for clinging to outmoded traditions long-since jettisoned by their trendier US counterparts, which prefer, say, to work out profits based on the cash you’ve actually got rather than crinkled IOUs written by some chap you used to play golf with.

One such tradition is the wearing of suits to the office – a practice, it seems, that can lead to culture-clash tensions in US firms’ City outposts.