I have Chrome and it works correctly on YouTube, but not in the embeded player. Urwumpe claims he has Chrome and Firefox and can watch correctly in the embeded player. Neither of us are guessing. These are observations.
Seems there might be more going on than just flash.
In browsers where Flash is optional you can (more or less) configure what Flash is allowed to do and what not.
On Chrome most of this settings are: "Yes to all", but can be disabled / enabled by user, so your mileage may vary.
On Firefox there might be options to allow or disallow embedded Flash videos to do all the things, too.
I almost completely "banned" Flash from all my browsers (due to all those security issues and update-hell lately). Chrome is still available for when I need something with Flash.
So yes, you can say it's something more than just Flash. It's a combination of Flash and user-settings. The browser itself being the most irrelevant part of it.
Nevertheless, let's say "I am wrong" and close this issue here (before this is beginning to go waaay off-topic)
:tiphat: