Originally Posted by
Duragrouch
I dunno about that. If, theoretically, you have a big enough difference in chainrings so that there is no overlap, then you start on the small ring, go through the entire cassette, switch to the big ring, then go through the entire cassette. Sequential. Bromptons are like this, no overlap. Low range on the IGH, 1,2 on the cogs. Medium range, 1,2 on the cogs. High range, 1,2 on the cogs. Zero overlap. And, the spacing between 1,2 on the cogs, is the same as the jump to the next range. So 6 equally spaced gears. I prefer no IGH, but darnit, they really did think out the gearing well. But they also have a special "Brompton Wide Range" IGH, not a standard Sturmey Archer 3.
People did stuff like this 40 years ago. And stopped. Bikes are semi trucks - you don't start in 1 and work your way up to 21. The reason this kind of gearing sucks is that we normally ride in the middle gears, which would make this a huge double shift all the time.
Alpine gearing where you switch back and forth big/small/big/small was also abandoned 40 years ago.
And then there is cross overs, which also suck.