I'm glad this was brought up because I'm always pondering if it would be more beneficial for me to stay in the small chainring most of the time with my lack of speed/strength. Typically on flats I find myself hanging out on my large chainring (50/34) and 21t cog in the back. I can easily hold about a 82 rpm cadence with this gearing. With some tinkering with gear calculators, I see that I can get the same gear ratio on the small chainring and the 14t cog. My worry would be running out of gears on the small chainring very quickly especially on rolling hills.

And now that I just rambled I highly doubt I made a point (or made any sense)...