Long-time reader, first-time writer. I watch too much foodtv and have often heard that to keep your knife sharp, you should slice green peppers and such from the inside, not the skin side. It seems to me that the thing that dulls my knife is its contact with the cutting board, not some wimpy vegetable. Whatcha think? Will I get an extra week between sharpenings if I follow their advice?
-- Slicing and Dicing, the net
The only TV the elves watch any more is Ground Force on BBC America, the show with the lady horticulturist who often operates jack hammers while wearing T-shirts without a bra. So I'm afraid we're not up to speed on the all-vegetable network. And the all-vegetable network must be running out of things to talk about if they've resorted to experts telling you to slice vegetables from the cut side. Sometimes having 200+ TV channels is no advantage at all. There is not enough interesting stuff in the world to fill all that air time, and your question is a perfect illustration.
A good sharp chef's knife has a blade that tapers to about the thickness of a sheet of paper, not hard to believe if you've ever had a paper cut. As the knife is used, the sharp edge actually begins to bend and curl. As the molecules get pushed around, the knife becomes duller and duller. The conscientious chef uses a honing steel before each slicing session. The steel helps push the blade edge back into alignment. Every year or so the knife may need to be sharpened, that is, have some metal ground off to create a fresh cutting edge.
Naturally, the harder the item you're cutting, the more the edge bends-- carrots bend it more than strawberries. So if green pepper skin is a little harder than the cut side of green pepper, then I guess you'll get more edge curl. I'm not sure it's measurable, though, especially if you don't eat dozens of green peppers every day. Personally, I think the all-vegetable channel has just run out of things to say and should consider showing reruns of Ground Force, always interesting, always educational, always braless.