Not even changes... if you care about 2 degrees or less, that may be within the tolerances of the machining of an aftermarket camshaft WRT the keyway on the nose and the real centerline of the lobes, that's why the instructions tell you to break out the degree wheel. (I would ASSume that if he's using a factory cam however the keyway or whatever is machined to tight tolerances, as degreeing in is not part of a typical factory engine assembly procedure.) And likewise with the TDC mark on the harmonic balancer or however crank rotation is referenced; since in the modern era timing is not usually set by a light but by the ECM using a crank position sensor, any visible marks may not be stamped/machined to the same tolerances that they were back in the day (and even then you had to take those readings with a grain of salt.)