You may have to increase the cache size of your browser to take full advantage of this functionality since some videos are larger than the default cache size, specially HQ (High Quality) and HD (High Definition) ones.
This also works for YouTube videos embedded in other websites and not just on the YouTube website only.
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Is your advice on increasing browser cache valid? Flash has its own cache, it’s different from browser’s.
It does, but you can find flash files in the browser’s cache as well. This is valid for IE as far as I know, where you can find Flash movies in the Temporary Internet Files folder.
right move for YT they cache all high traffic pages now cache video also great