Actually while Chrome 38 gives me a terrible dt variation (typically 8 - 45ms), Chrome Canary seems a lot better, ranging only 21-24ms. It also subjectively looks better - it's not perfectly smooth in Canary (obviously, since at 45 FPS there's no choice but to skip some frames), but it doesn't have the eye-straining extreme juddering which Chrome 38 has with its wide dt variation. So it may be that it's already been fixed and we only need to wait for Canary to come through (currenty v40).
Can anyone with affected games give them a spin in Canary and say if it seems any better? You can install it side-by-side with normal Chrome: https://www.google.co.uk/intl/en/chrome/browser/canary.html
Canary might have also improved the input latency so you can test that with it too.
BTW in the test I posted earlier the rectangle count is completely irrelevant, it's only aimed at measuring the dt variation.