Plus, just having greater numbers does not mean you autobreak, you must actually win the combat as well. With how outnumbered your units will be, you'll be getting flanked and that sort of thing, and not winning any combats.
Its not as hard to end up outnumbering cavalry, so smaller elite units are the sort of things we can autobreak. For block infantry, the most reliable method of breaking them is to flank and negate their rank bonus, and get as many ogres in B2B to maximize your wound output and win through that method.
I personally feel that a more standardized 2k list is "better" but its certainly debatable, and people on the Ogre Stronghold have had moderate success with Skragg lists at GTs.