I have two tags as a General and it's not a problem for me to be in more than one squad, but that's because I understand my role in each of them. I've seen where some people can and often do spread themselves too thin trying to do too much. I would say that if a Captain is to have more than one tag then it will be helpful if their responsibilities are clearly outlined when they're told they're wanted to just "Help out" in the other squad. Captains are supposed to run the day to day stuff in the squad and they can't do that everywhere, so as long as it's just for training other Captains in another squad I don't see a problem with it, but then again, they can just send the other ones a friend request, right?
As a General I'm told to network with others and seek the advice of my peers when faced with a tough decision and when I do this, I don't have to create another tag and put in their squad first.
I understand that there's times this may be neccessary but I'm just saying I believe it's less often than others may think. One of the reasons I think INNOVATION (My main squad) is running smooth is because I don't spread my Captains too thin, and don't over burden them with other things.
If Generals promoted well, and according to someones leadership abilities instead of other reasons, then this wouldn't even be a discussion topic, so when someone says they need to "borrow" a Captain, where's the real problem? This is not meant to imply anything, but it is something that has to be asked. If my Captains weren't doing their job, then am I as a General who put them there? I wouldn't ask this at all if I didn't hold myself to this standard. As a General, if someone is having trouble doing their jobs, then I need to know if I did mine first in training them BEFORE I promoted them.
Again, if there's someone that's good enough to let them train others, then it's fine, but there's seldom a reason they would need a second tag for that.