Hi there! I'm new and I know a very kind lady put up instructions for her spiral cake. I am about to make one and wondered if anyone had tried a different technique of just baking the cakes bigger than necessary and then carving a spiral into it maybe only adding extra cake for a teeny bit? I don't really have the time to make it twice, so I just want to set out which way to go first. Any ideas? Thanks!!

You could try it with cakes that are larger than necessary, but why waste the time baking more only to have more waste? If you're referring to these instructions,
http://cakecentral.com/articles/662/how-to-carve-a-spiral-cake
I don't see why you wouldn't want to flip the carved away section(s) over to incorporate into the design rather than throwing it out. It's a perfect fit, and also saves time over carving from another piece.