Originally Posted by
Kimmo
Some slight suspension would make up for the greater impedance (losses from bouncing the bike and rider up and down) from the smaller wheels.
I fully agree with this: on bad roads and cobbles, a road bike suspension with short travel like on the Moulton or Birdy and nowadays several road bikes (main road bike manufacturers like Specialized, Cannondale, Trek... have now road bikes with suspension systems) make the bike more efficient..
Bouncing from one cobble to the next reduce the bike efficiency !
Note that road bike suspensions aren't the same and behave differently than mountain bike suspensions.