This is kind of a combination mechanical/physiological problem, but I've been noticing lately that my right hand thumb has been pained by the action of switching gears at the front. It could just be that I'm getting old :\ I have to take my hand back off the bars a bit and push the lever with a straight thumb, or it's just all pain and no go. Clearly the cable could do with a service, but I'm not convinced that that is the problem.

Anyone experienced anything like this?

I've even considered getting electric shifters, but I don't know whether that would be worth the hassle.