1) Video on a DSLR is here to stay
2) Video costs on a DSLR is neglible to say the least, Canon had video figured out a decade ago, and once they added Live View to DSLRs, video was a no brainer
3) Video on a DSLR does NOTHING to your still capabilities
4) If you don't like it, don't use it. In fact on cameras like the 1D4 and 5D2, it is so hidden that it is easy to even forget it has video, unlike the 7D and 5D3...
I would postulate that adding video decreases the cost of cameras considerably, simply because it is a feature that sells more cameras. A stripped down stills only no frills camera would be a small production niche market item, and probably cost a lot more.
i agree. fragmenting the model line like that would raise production and marketing costs, and inevitably costs to the consumer.