Board Thread:General Discussion/@comment-5065259-20131018231016/@comment-11733175-20131019103833

I believe anything cross wiki causes a lot of server strain. It's why staff stop us using signature templates stored on central on every wiki.

As JS is client side I see no reason for it to be against ToU, although there are various security concerns that would stop me implementing any such script. Why not just add a notice requesting people use your other talk page instead?