Re: Rapid Dimension specifically for Sheet Metal...
I also consulted my colleague in Product Definition team and got the same answer as Dave Wingrave has given in the post you linked to.
I'd like to offer a possible solution for you:
Customise the view radial menu and add linear and radial dimensions to it. This way, the correct dimension command can be directly selected with a simple mouse gesture. I've shown this in the attached movie file - of course you don't need to wait for the radial to show, I just did it slowly for you to see what I did.