There is something funky with the last one. They all have the same percentages for the first two gears even though the last one has different gears.

I think you should have made the calculations with 9 speed cassettes instead of 10 speed because the majority of us run 9 speeds (or less) and maybe included the 11-28 that many of us use.

As far as the perceived perceptions versus non-perceived perceptions go, I think a lot of if has to do with what you are used to. I've run the larger cassettes on the Santana we used to ride. Most of the time it was fine but there are times when it was really annoying to be caught between gears. That just means you have to slow down or put more effort out to speed up to get in a more comfortable cadence. I run an 11-28 or 11-25 on my single so the 11-28 on the tandem is just like home.