2min rule on a S/M item ?

[cwoodgold]

So if you are at the office, and you process your inbox and you come up with a 2 minute action, but you can only do that 2 minute action at home, then what do you do?

I believe David Allen's 2-minute rule applies to actions you're definitely planning
to do and can do right now -- that is, to actions for the context you're in.
So, as you say, 2-minute actions for other contexts go into your system.

I also generally apply the 2-minute rule when I'm recopying lists of actions.

That's a good idea, labelling them as 2-minute actions. I might do that;
or, I might not, because I might like to re-assess each time how long it will
take. For example, I might decide to write a short email instead of a long one,
or vice versa; and besides, my cutoff can be longer or shorter than 2 minutes
at different times.