Hi Tim,
Bar-end shifters are not for me, I can imagine the difficulties in the very hilly areas f.ex. New Zealand where I was using shifters very often.
Is your description to be understood in the way as shown here?
http://www.panniers.com/technical/shiftersBB.asp
If so, yes itīs a possibility on the tour, but using the bike as your common means of transport without the bag, it looks a bit foolish I think.
Per