The best and most practical solution would be letting KWin do a series of small tests when noticing the OS freshly installed, an update to drivers(other relevant software) or device change.
(Default on) So KWin can send automated bug reports and inform the user.
(Why is everyone having such a hard time figuring out what to do in a case like this?)
More tests on Mesa wouldn't hurt either.
(Hint: Including starting multiple apps that use the card to see if they mess up.)
In any case, the result of glGetString(GL_RENDERER) is *not* part of the ABI and should not be relied upon (it *will* change from version to version). The Mesa devs have shouted this time and time again, yet some people still manage to get it wrong.
I assume Martin has already updated the KWin compositing whitelist to include the new Intel driver. So biggest problem here seems to be that Ubuntu (and perhaps other distributions) are unlikely to provide the KDE update in a timely manner?
Also, drivers lying about their capabilities should be regarded as a critical driver bug. I'm not sure that it's reasonable to expect a window manager to handle that gracefully. Again I assume that driver bug was fixed fairly quick, and that what made it a big problem was that Ubuntu (and perhaps other distributions) were unlikely to provide the driver update in a timely manner.
To me, these are just more reasons to prefere rolling release distributions. They get updates and fixes to their users as soon as possible.