While I'm on the subject can anyone explain why touring bikes allies bar-end shifters.
Simple answer is that it's the only way to use modern mountain bike gearing with drop bars. Shimano used to have the same pull in their mountain and road group derailers. That meant you could use road shifters (STI) to shift mountain derailers in the rear (with clusters over 27 teeth). When they went to 10 speed, and now 11, the pull ratio was different between mountain and road. You can still get by with STI and 9 speed gearing if you can get the parts, but the bigger bike manufacturers are slowly tossing in the towel and going to newer models for parts availability.
Bar End shifters were popular on touring bikes before Shimano introduced a different pull ratio in Dynashift mountain bike groups. I suspect Bar End shifters were a reaction to down tube shifters.
In Shimano's implementation of the brifter, you end up with a very complicated and non servicable mechanism. I cannot speak for non Shimano brifter implementations, but I suspect they are also complicated and not servicable. Shimano brifters can stop shifting due to gunked up lubricants and wear. A Bar End shifter is a much simplier, and much more reliable mechanism. As longs as nothing fractures in the shifter, and there are a least a couple of strands of metal in the cable, a Bar End shifter will shift. Plus you have infinite trim points on the front derailleur and non-indexed shifting should something drift or stretch.
I have 9 speed Ultegra brifters on my Paramount, and one of them recently stopped shifting. I had tried all of the documented tricks for getting my brifters working again, including 20 minutes of flooding it with citrus degreaser followed by water followed by wood alcohol, and then more degreaser. I thought about going to Bar End shifters, but ended up buying a set of Micro-Shift shifters. The Micro-Shifts are ok, but not as smooth as the Ultegra's were. I gave the Ultegra's to a buddy who was going to canabalize them for parts. He got them working again, by giving them a long soak in an ultrasonic degreaser. I have a lot of cool stuff but I don't have an ultrasonic degreaser tank.
If you want reliability, get Bar End shifters, as brifters are a crap shoot.
A touring bike does not need the responsiveness of a race bike. I will take the time it takes to move my hands to shift in exchange for a more reliable mechanism.