I'm running a 26 X 30 low gear on my single and a 26 X 40 on our tandem. 1 X 1 used to be OK . I went to this ratio on my single at about 70 and the low ratio on the tandem at 75. At 69 & 65, we rode RAMROD on the tandem with 26 X 34. Cayuse Pass was hard but we finished strong. I do long climbs at about 83 cadence on my single and 78 on the tandem. 175 cranks on the tandem, 170 on the single. I don't notice any difference in crank feel between the bikes.

If 145mm were the most powerful setup, the pros would all be using it, i.e. there are drawbacks. My experience with cadence is that oxygen consumption increases with a higher cadence at the same power. That improves somewhat with specific training but doesn't go away. That might mean though that folks with a very high VO2max could benefit from shorter cranks. I think we saw that in the last TdF.