Hi,

You can certainly start faster with the seat at the right height
and the correct mounting procedure compared to those that
can stay in the (too low) saddle at lights.

Away from the lights the "too low saddle" types usually have to
stand up to make better progress than me in their default gear.

Mounting you start stood up and set off very quickly, especially
if you don't go immediately to the saddle, though I usually do.

If you have a short urban commute its probably best to set saddle
height so your toes can reach the ground, it is just safer, and
probably set up the bike for a relaxed riding position.

Only on longer rides will you really notice the effects of
good seat height and better riding positions and a few
other things, like nice tyres and a better saddle *.

rgds, sreten.

* A great saddle for commuting isn't a great
saddle for touring much longer mileage usually.
The other way round does work better usually.