A lot of people think that, but I don't see it working. Incognito mode hides your search history, but sites can still see your IP address. Prices change more from how many people are booking than from your own clicks. I've checked both ways and the prices were always the same. It just seems like one of those internet tips that doesn't pan out.
Noticed this pattern with a lot of online advice. In my experience, things like cleaning hacks or cooking shortcuts often don't work as promised. Take those viral towel-folding methods, for example. They look easy in the video but end up a mess in real life. Your mileage may vary, but we tend to trust these tips too quickly without testing them ourselves. It's similar to the incognito mode thing, where a simple idea spreads but doesn't hold up.