not sure I follow you. Sorry, I've been an off and on biker so some of the terminology is not familiar to me. Fixed what? Gear ratio? Are you climbing hills on a track bike? The power difference in what is noticeable? Your new pedals vs. your old ones, or road bike shoes vs. mountain bike shoes?
How far would you have to walk in road shoes to mess up the cleats?
Yeah, he's talking about a "fixie", a fixed-gear bike. And he meant that, with clipless pedals, he noticed how much extra power he gets (everyone should - it makes a significant difference).
For my LOOK cleats, they just gradually wear down from engaging/disengaging and walking. The more walking you do on hard surfaces, the sooner they wear down and need replacing. SPDs are much smaller, but it's still essentially impossible to walk around normally in road bike shoes, hehe.
MTB shoes (mountain bike shoes, the kind commonly available with recessed cleats) vary in their weight, as do road shoes, but equivalent price-point MTB and road shoes would be very different weights. You can look up any online bike store and look at prices and weights of their various shoes. If you're planning long road rides, you might find that the extra weight on your feet makes it a bit tougher. But realize that there are lots of "weight weenies" as they call them in the biking world! If you don't care about riding a steel vs. aluminum vs. carbon fiber framed bike, then don't worry about the weight of the shoes. People on bike forums often get obsessed about decreasing the weight of their bikes. For commuting, I use a really old but trusty Bianchi that looks quite awful (I like to think it's a theft deterrent
). It's a steel framed bike, heavy enough that I wouldn't care if I was using MTB or road shoes with it because they won't make that much of a difference anyway with such a heavy bike. For training and racing, I have a Softride TT Classic, which is a speed demon and MTB shoes would proportionally make a bigger difference.
The point is - if you're not worried about minimizing the weight of your bike (and you're using it for commuting/fun as opposed to racing), don't buy into the weight hype about shoes. If being able to walk around normally, go into a store, etc, is something you value when biking, then absolutely go for it. Dedicated road shoes would only be worth it if you're really going for speed, getting a nice lightweight bike, doing big climbs and long distances, etc.