But really, I enjoy my bar-end shifter bike as much as my Ergo shifter bike, and which shifters I use makes approximately zero difference in how well I climb.My personal objection to barends (and yes, I have them on one of my bikes) is not functionality but accessibility. The work well but I find them very difficult to get to if I discover I need a lower gear in the middle of a climb. If you can anticipate your shifts and shift while seated, fine. If you are surprised by the grade and need to shift while standing, they are awkward at best.
STI/Ergo and "Retroshift" brifters can be shifted any time with minimal hand movement so being in the wrong gear can be corrected immediately.