Last night I was honing a Crown & Sword which had a LOT of spine wear, so much in fact that I couldn't get the thing to get sharp at all, it seemed like the pine was to thin to produce a nice angle for the edge. Anyway after setting the bevel with a shapton 1k and finally getting it razor sharp (funny) a revelation came to me, the bevel was even but the spine was by not any means even.
What this means according to my imagination is that sometimes the spines on newer razors or vintage ones might not come evenly ground, thus producing small irregularities on the edge which in turn translate to uneven hone wear and weird bevels. So I taped the spine on an Imperial razor which had some uneven bevels and uneven spine wear and Voila, the bevel is now straight as can be and produces a very nice shave I might add. So for those thinking that Taping the spine is to preserve only the spine think again, it might actually be a way of producing an even bevel on some razors.