shelbyfv:
Yes, on this bike (Black Mountain Cycles monstercross frame), I started with the CX70 front derailleur, so I didn't try it with a standard road FD.
However, I've also set up my old Trek 850 mountain bike commuter with a 46/34 crankset. This is a true Frankenbike setup:
-- Shimano Sora crankset (9-speed) on Hollowtech II bottom bracket
-- Customized 9-speed cassette (a 12-25 changed to a 13-29)
-- KMC 10-speed chain
-- The original 6-speed Shimano Deore derailleurs
-- Shimano Deore 9-speed trigger shifters from eBay
The FD is designed for a triple crankset (profiled inner cage), and at first it would jam the chain against the inside of the 46t big ring and refuse to up-shift. But I raised the FD until the inner cage profiling lined up with the top of the 34t in the way it used to with a 28t inner chainring. It took a little fine-tuning, but now the cage profile helps squirt the chain up to the 46t, and it up-shifts quite nicely. A different scenario, perhaps, but at least it tells you that there are lots of ways to adjust non-standard combinations to make them work fairly well.
Also, the dramatically better up-shifting with my new 46/30 setup compared to the original 46/34 setup shows how much difference the ramp and pin design on the bigger ring can make.