Originally Posted by
79pmooney
I was raised on gear inches. For about 20 years they were totally out of style. Many in the bike world wouldn't have a clue what I was talking about. Those who knew looked at me like i just brought up a tyrannosaurus rex. GI is back in style. Thank you! (The one gear notation that includes wheel diameter.)
Here is my take on that topic...
Back in days of 6-speed cassettes, to cover a wide range, the gap between adjacent gears was larger than today to cover same gap with 9 or 10 speeds. This and an associated concept of half-step gearing meant that it was helpful to see how your gears lined up and how much duplication there was in adjacent combinations. So I can see it being relatively more important to understand placement of those combination. With more gears overall today coming from cassettes, those overlaps are less of an issue.
On the other hand, knowing the range from highest gear to lowest gear (particularly for bicycle tourists) is still an important aspect to know how your setup works at the extremes.