Its twisted steel structure has provoked endless conjecture about its purpose.
Laura Robson's latest coach, the uncompromising Zeljko Krajan, says the British teenager "doesn't even know herself how good she is".
In the past they may have felt overwhelmed at the prospect of following Team GB's world-beating sailors.
There were no tears, a few smiles (especially when he mused about becoming a new cricket correspondent for the Sun), and much dignity.
Andrew Strauss used to be a fine rugby union fly-half as a student at Durham University, with "a prodigious left boot – a real howitzer – a silky set of hips for the big guy he actually is, plus great hands", according to the coach who tried unsuccessfully to persuade him to give up his cricket 15 years or so ago.