Among the various issues I've seen:
* Sometimes refuses to play anything, without showing any errors, requiring a reload of the page.
* Occasional poor performance.
* Audio/video desynchronization
* Scrubbing the video often causes it to get stuck, refusing to play, until I scrub it again
* Videos often take longer to start playing than with the flash player.
* Fullscreen is sometimes broken
* Switching from regular mode to "theater" mode sometimes leaves the video playing in its original size, anchored to the corner of the now-larger black area that it should be playing in.
I think it's gotten a little better recently (i.e. I see issues less often), but it's still far from great.
And before you ask, I've seen these issues in both Safari and Chrome.
As for the issues you're experiencing - are you sure you have GPU acceleration turned on?
I'm using Chrome and CPU usage is only 45-50% for perfect 1080p 60FPS playback.
Not on older (3y+) machines.
> make me think of some kind of adobe shills maybe
Delusions or paranoia may be?
Also 9 year old is quite a frac cry from your initial post of "(3y+) machines", 9 year old machine almost guaranteed has absolutely no support in hardware for modern codecs. So no wonder has strong limitations on resolution. Still flash working better than HTML5 players is still suspicious to me, I still believe with correct configuration reverse should be true, as flash is basically just another layer in between screen and bits on the net. Though possibly not applicable in all cases.
> Still flash working better than HTML5 players is still suspicious to me,
Do you write programs for life or what? It is not a problem with HTML5 players, it a problem the way they are written. Flash is an older product, with better support of legacy or underpowered products.
> I still believe with correct configuration reverse should be true
Yes, the correct configuration is "more powerful CPU".
For reference, I use chromium (not chrome) on Linux (which does not come with flash bundled).