I see what you're saying about Razor Edge System's sharpening guides but as far as being flawed I do tend to disagree with you. Because I've used both my Razor Edge Sharpening guides on small folders and big fixed blades ( usually no longer than 6 inches or so) and I've found that where you position the guide on the spine area of the blade is what determines your overall degree of angle.
Because I have both the guides i.e. one for blades under 4 inches long and one for blades over 4 inches long and I've had some really decent results using them along with high quality benchstones. It really boils down to where you position the guide on the spine part of the blade. John Juranitch ( the owner of Razor Edge Systems) has written a great book which shows you how to use the guides ( both the book and video are on their website) and he's also done a very informative video on it as well. If you could check out either one or both of those I can assure you that it will shed more light in the uses of those guides.
I'm actually surprised that Spyderco hasn't come up with something like that with all the very nice innovations they have come up with.
