Hi Threeson,
I designed the knife to be used. I carry a Caly 3.5 quite often.
If you have limited sharpening skills, you might consider a Sharpmaker. ZDP is very hard. Sharpening at the 30 degree on the sharpmaker works well.
sal
I do have a Sharpmaker and I use it after using my Fallkniven DC4 (diamond/ceramic) if the edge is in bad shape. If it's in relatively good shape, I go straight to the Sharpmaker stones. I've, in fact, been practicing freehanding on the Sharpmaker using the slots in the back (thanks for including that feature) and by holding a single rod and using a back-and-forth motion. It's very fast, but it also requires a fair bit more practice to master.
Back to the Caly, I have to say, that as an individual with two engineering degrees (B.S. Mechanical, M.S. Environmental) and another master's degree (Environmental Science, Policy and Management), it is so refreshing to encounter good design principles AND good fit and finish your products. My engineer's heart is warmed every time I snap open the Caly3 just as much as it is when I close the valve on a German-made Grohe kitchen faucet, measure clearances with a Mitutoyo caliper and sit astride my Triumph Bonneville.