Not necessarily a bad thing but pulling in the shears at the middle will also affect yr keel line. You will want to be careful pulling in the shears at the middle too much as you will be eliminating rocker or even causing canoe to hog (stems deeper than center) which is not a desirable condition. I have only observed this on a Royalex boat myself but was actually a very good effect. It was done to a small tandem with probably 3 inches of rocker originally. When the gunnels were pulled in abt 4 inches it made a fairly straight keeled solo with a fair amount of tumblehome.