I got inspired so today I made the cake as outlined on the link above...
I'd never made a red velvet cake the "authentic" way before (no red dye, no cocoa). The results are delicious but it tastes more like a "spice cake" than the red velvet cakes I've had from mixes and at bakeries. Also, it doesn't come out blazing red like the bakery and mix ones do either; more brown with a pinkish tint. After looking around online I found some photos and apparently the brown with pinkish tint is normal.
If you like chocolatey and unmistakably red cake then stick to standard red velvet mixes or just add red dye to your favorite chocolate cake recipe.
You are 100% correct about the origins of red velvet cake having to do with beets! During World War I there was a ration of cocoa which made it difficult/impossible to get cocoa to make chocolate cake. Some inventive cook substituted pureed beets which with the vanilla makes taste that, although not chocolate, is better than nothing if there aren't any other options.
Obviously there isn't a chocolate ration any more and has not been for a long time but people fell in love with the look of red velvet cake. It is now become essentially a devil's food cake with a dash of vanilla and as much red dye as the cook can get their hands on.
SO, if you're looking for a recipe that tastes like modern red velvet cake then you'd most likely want to use a recipe that calls for cocoa and just substitute beet juice for the red dye. Here is a link to a possibly more "authentic" i.e. no cocoa red velvet cake recipe that Tyler Florence made on The View. http://www.food.com/recipe/tyler-flor...