Originally Posted by
cyccommute
Can he get the same ratios with a double as with a triple? My answer would be no. He can get the same range. But he's going to be missing ratios in the middle of that range that make the transitions from high range to low range smoother. No choice of cogs or chainwheels is going to change that.
If you want the range AND close gear ratios, a triple is the only way to go. If you don't want one or the other, then you can do a double.