Ok, so your point about it mostly adding cogs in the slower/faster whatever part of the cassette and needing special housing was gibberish. Glad we cleared that up, because the arguments you're making now don't appear to be the same ones you were making earlier.
Old 10 speed, including 5600/6600/7800, all SRAM 10 (3.1mm/gear) and all Campagnolo 10 (2.8mm/gear, also the oldest 10) shifted fine. Saying old 10 speed is still an over generalization. It's true that Shimano 10 (2.3mm/gear) is less than Shimano 11 (2.7mm/gear) making it more sensitive to cable friction, but the fact that 5600/6600/7800 had external cables greatly reduced friction in the first place. No small radius right angle S-bends at the bars. Both the SRAM and the Campagnolo have cable pull per shift at least as good as Shimano 8.
I'm still going to disagree with you. Only with 2nd generation Shimano 10 is where there was a problem, because it has the increased susceptibility to friction because of the 2.3mm/gear pull, and it had increased friction from under the tape cables. The friction from external cables to under the tape cables is not insignificant. It's that in combination with the pull ratio that causes the issue, not the pull ratio alone. Even then it still shifts fine.
Does bending a derailer hanger it bother the 10 speed riders? Apparently it bothers 7/8 speed users who don't use 10 speed and bend their hangers on a regular basis.
Obviously what cogs you have depend on cassette choice. If you don't want tightly spaced cogs, you can get a wider cassette. Compared to the 13-26 you chose, you still get to keep your 13-14-15, not only that, you get wider spaced cogs at the bottom end and lower climbing gears. Sure they're useless if you don't climb steep stuff. But it's not simply more cogs in the slow part of the cassette for racing, whatever that's supposed to mean, or tighter cogs for people that that want them, there's also the option of wider range.
12-13-14-15-17-19-22-25-28-32
vs
13-14-15-17-19-21-23-26
As far as cost goes, only the buyer can determine if having an extra cog is worth the cost.
Last edited by 2lo8; 07-21-16 at 03:22 AM.