Now, though, it is being messed up. First, the beautifully worked out patterned paving (constructed, it seems, on a proper sub-base, unlike the sightly, but collapsing, block paving schemes in St Martin's Lane and Cowcross Street - another lost art) began to be replaced by repairs of the messiest kind, tarmac in some places and concrete in others, according to the whim of the perpetrators...
More recently, ranks of huge new blocks of granite have been placed on top of the paving, presumably as an anti-terrorist measure...
..located according to some sort of notional plan, but only approximately, with most pieces a bit off square, not quite lining up, and not aligned with the paving pattern. They are not fixed, but perhaps were too hard to shift once they had been unloaded.
It seems crazy to spend the money on honed granite blocks and not place them properly - better to do it in concrete, and spend the money saved on some more diligent builders - or supervisors.
You can't fight entropy, I guess. Ordered systems inevitably become disordered. Reading Stewart Brand's 'How Buildings Learn' should be enough for anyone to get over the idea that you can make a project perfect on day one and hope to keep it that way. But like most architects, I hanker for a built environment that is better organised than the one we are given. The Royal Borough of Kensington and Chelsea, of course, now have more important things to worry about - and it now looks as if the money spent on paving Exhibition Road would have been better spent on refurbishing tower blocks properly.
But here as at Grenfell Tower, this is not just about money - it is about doing things thoughtfully and carefully once the resources have been committed.
Thankfully, you can raise your eyes from the streetscape and cheer yourself up at either end of Exhibition Road, with two recent projects.
At the V&A Museum, AL_A's project to connect Exhibition Road to the central courtyard succeeds in that main objective, and as with so many public projects, it is good that it has happened at all in these straitened times - but it is done via some odd moves along the way. The project's new entrance courtyard shares with the practice's MAAT museum in Lisbon a white tiled paving that produces enough glare to be uncomfortable without sunglasses on a sunny day - here, it would be good to find the ravages of time taking a bit of gloss off.
Francis Kéré' s Serpentine Pavilion, at the other end of the road, is one of the best of that series - joyful but rigorous, masterly in its control of geometry, and free of the whimsy of some of the gallery's offerings of recent years.
Serpentine pavilion architects, of course, don't have to worry about entropy - the project is taken down before it can set in.