I don't know if this is common knowledge, but I only figured it out last night so I figured I'd share for those who aren't aware of how to do it.
If you've ever tried to copy and paste a bunch of keywords into the tags box you know that it'll only register the first keyword in the list, leaving the rest out and leaving you to type every single keyword every time you post a new video.
WELL NOT ANYMORE!
If you type your Keywords into Notepad separated by commas and a space, for example "let's play, gone wrong, gone sexual" (without quotation marks), you can then copy and paste them into your tags box and it'll add all of them.
Happy tagging!
TIP: How to copy and paste multiple keywords into your tag box
Copy and Paste Tags
view your video with the tags on the watch page right click 'view source' then search (ctrl f) for 'keywords' in the source page. Copy them and paste. annoying but yeah
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