The problem is that DSLR lenses don't AF efficiently with contrast detect AF.
All that is needed for a PDAF lens to work well on CDAF is a proper algorithm, a proper electric motor with gearing and a proper sensor read-out.
There is no physical restriction prohibiting this to be developed.
All the lens needs to do with CDAF is to be able to focused in and out smoothly. The nice thing with most of Pentax's lenses is that the motor sits inside the camera, so a Pentax EVIL can easily fulfill the above-mentioned requisites.
Now, SDM lenses, that
could get more difficult.
Maybe! As far as I can see, no one here really knows how the SDM motor driver algorithm works and how much is in the lens and if it can be bypassed or not.
The body size would be larger than the competition.
Marginally. Also, body size is only part of the reasons why people are after EVIL. Generally, looking at body size and not system size is a dangerous (but admittedly tempting) mistake.
You are still assuming that Pentax would design the EVIL camera to have the full K-mount register and not opt for a rather simple adapter from a µK to K. Going this route would allow using basically any lens.
Even in an EVIL with full K-mount register, the "dead" space does not need to be "dead". You can create collapsible lenses using that volume. Or develop optical filters placed between lens and sensor. Either would work towards making the system more attractive than the "dead volume" solution you are fearing.
The K-mount also limits the number of manual focus lenses that you can use (such as all rangefinder lenses will be unusable) due to larger flange distance.
Well, if you were right and Pentax would go with the full K-mount register, you'd be right, but even then: It could be a deliberate decision to make people use Pentax lenses on a Pentax body. You know, what most manufacturers want. Apart from that, while I like to use old lenses on my cameras, I feel that the average buyer puts pretty little importance to cross-brand backwards compatibility.
The real risk for a K-mount EVIL, or rather µK Evil is that a mechanical mount like K or µK (if we want a simple adapter from µK to K) is rather expensive and all recent mounts have been electric&electronic.
--
'Well, 'Zooming with your feet' is usually a stupid thing as zoom rings are designed for hands.' (Me, 2006)
'I don't own lenses. I pwn lenses.' (2009)
My Homepage:
http://www.JensRoesner.de 
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