On my commuter road bike (700c) my large front is 54t and my rear gearing is more like a touring bike..... 12-26. I pretty much never ride in my small chainring so I won't mention the size. Only time my chain is on that ring is for a two minute warm up and cool down, or on the off chance I cut cross-country for a short distance.

Our street conditions are so poor in general that staying in the large chainring eliminates a lot of chain slapping and ghost shifting when hammering along on these Paris-Roubaix surfaces. I take routes on 700x23c tires that friends of mine won't even ride on 700x32 rubber. They won't use ATB fattys either, cause it is too hard to keep up with traffic - some routes are "do or die" fast cycling required. When I sometimes try my ATB on these routes I spin out in my tallest gear, wishing I had one or two more. Horns are ablaze and fists clenched if I drop much below 25mph on some hellish roads.

To answer your question with an OPINION....I don't think ATB gearing would be advantageous for me on my current commute. I am out of the saddle from every stop, so I never drop down to my smaller ring once the battle begins.