Bigger rings are more efficient?

I haven't done an A/B comparison but I think I can tell the difference between 73" and 74", sensitive soul that I am. I think perhaps because it's on the borderline between comfort and work.

I dunno... 1" doesn't seem so much? I recently dropped my chain ring down a couple of teeth from 48->46 (3gi) for the same reason. Feels much nicer - now I'm used to it I find myself spinning a little faster and lighter on flats but (more importantly) hills feel better - don't think I would have noticed this with only 1". I can now make it comfortably around the Dulwich Paragon Saturday morning ride (SS not fixed) - but there's one small hill that's still borderline - I reckon th extra 3gi would have me walking up it? Love your knees...