See ... I have crashed going uphill because I've been going so slowly I didn't have time to unclip. Crashing reduced my already low confidence level in my climbing ability, and so I started walking up everything in sight, even when I probably could have cycled up. I just didn't want to risk crashing again.

When I switched to the setup I use now, my confidence level increased, and I'm cycling up everything in sight!! I know that if it happens that the hill becomes too steep for me, I can easily put a foot down. But I rarely come across hills that are too steep for me anymore.

Another benefit of the setup I use is that I can negotiate the traffic in cities better ... especially European cities which tend to be very congested.