Well, I must admit that I religiously lap all my hone stones and synthetics. I have lapped guanxis, barber hones, arkansaw, indian orange, tos, dalmores, idwall, cf, and translucent arkansas - to name but few - and have seen the demise of not more than a few DMTs in the process. Mind you, I no longer need the bull-worker for my arms. Guanxis and hard arkansas (or any novaculites, of which the cf is one) are DMT killers.
The reason for frequent lapping (to my mind and my method of using hones) is simple - I use a number of different hones in combination, and they exhibit different degrees of wear. If they were all like DMTs - no problem - but they are not. Some wear (ie dish) faster than others. Some synthetics (naniwas and shaptons) exhibit swell/shrinkage in different areas. Some razors need the heel worked on more than the toe - others vice versa, leading to exaggerated wear on one part of the hone. So - with a dish in one place of a particular hone part of the bevel is not being honed, and with a dish in a different place (or less of a dish, or no dish, or a swell) then a different part of the bevel is being honed (or not honed).
Something needs to be a constant, or you can't assess what is happening. If wear is not a constant among different types of hone then it has to be brought under control, hence frequent lapping.
The trouble is that not all hones are the same, and as I restore razors 99% of the time I have to use quite a number of different hones, from rapid metal removing hones, to bevel setters, to finishing hones. In this arrangement I need to have a constant, and that is the flatness of the hone.
If I used but one stone (a japanese natural, or a yellow coticule for instance) then I don't think it would matter as much. The bevel would degrade the hone in the same proportion as it was being abraded - if that makes sense. If the dishing of the hone was a constant and was in line with the bevel of the blade, then I can see that there would be little or no problem (unless I used the hone for a number of different razors which exhibited a range of tempering hardnesses). With light use (eg one razor and minor maintenance work and a hard natural hone stone) I would imagine that lapping would seldom be necessary.
In short, what works for one person is the thing (for that particular individual) to stick with - if it isn't broken, why attempt to fix it? (or to paraphrase, if it doesn't need lapping, why lap it?!).
BTW, I agree about the need to soak a C12k - I have left a puddle of water on one (OK, more than one - about 12) and it was still there after an hour. As far as I am concerned - with C12k guanxi stones I have become familiar with - soaking is absolutely not necessary. I do reserve the right to change my opinion when I come across one that drinks up water, though!
Regards,
Neil
