Well I don't understand it either - I'm a full-time accountant and part-time singer/guitarist/mandolin player, not an electronics Graduate, FFS! But I have it on good authority from someone who does understand electronics that its the case, and it was certainly the case when I tried using a Baggs Para-DI with my K&K's. Not successful at all, not to my ears, so I sold it to a pal who has UST's in his guitars. However, K&K produce a matched pre-amp that works superbly with their pickups (as you would expect).

Ralphie - I'm quite well-acquainted with Martin's gear, and you're right that he has an awesome sound (not to mention the fact that he's a mind-boggling player, and I say that from the unenviable position of someone who had to follow him on at an event a few years ago!). But it comes at quite a cost (and I guess you know all about that, as you have the same gear!). I'll have to satisfy myself with K&K's and an Orchid DI box - my bank account insists that it's so! :-)