Comparison to an ordinary or penny farthing is entirely appropriate. The gear inch concept was invented way back then to convince people who were used to riding the large wheeled bikes that a "safety cycle" with small wheels could be geared to give them the same performance. Every cyclist of that day was familiar with the effects of wheel size so the gear inch equivalent was a perfect way to get the point across. These days gear inches are just numbers to those of us who are not familiar with large wheel cycles but they are perfectly useful numbers even though we don't have the tight experiential bond to wheel size that existed back then.

It is also correct that the large gear inches are useful mostly for downhill runs. With a top end in the mid 90's you just have to coast down hills that are very steep. People who want to pedal as hard going down a hill as up it will frequently need those high gears in areas with steep hills. If you are content to coast, you do not need the high gears and might wish that you could have lower gears. In fact you can, just change out the chainring to a smaller one and you can shift the range downward. The ratio between the lowest and highest gear will remain constant but you can set the low gear where ever you want it within reason. If this model had only the rear cassette and a fixed speed hub then the total range in gears would be the largest cassette gear divided by the smallest. With the rear hub available you multiply that range by the largest hub ratio divided by the smallest. That is why this model has more total range than models that lack the Dual Drive rear hub. Nothing new here, I'm just reinforcing what has already been said.

Now you can get the same effect from a front derailleur as you get from the Dual Drive hub. When you have an FD you multiply the range of the cassette by the largest chainring divided by the smallest chainring to get the total range. The Vitesse has an FD in fact but it has only two chainrings that must be fairly closely spaced since it has very little more range than Dahon's 7 and 8 speed models which have neither the FD nor the DD hub.

If you want to supersize your gear inch range you would start with an 8 speed model and put a Schlumpf High Speed Drive on it. The HSD will multiply the range of the cassette by 2.5 and a Dahon standard 11-32 cassette would give you 16-118 gear inches. If that is not enough you could put a Capreo rear hub on the bike and modify a Capreo cassette to 9-34 teeth, giving you 15-144 gear inches!!

Ken