The XC15 4K
Camcorder uses DiGiC DV III's for h.264 output and has to be vented. Canon's cameras do not use DiGiC DV's .. but different DiGiCs.. good lord. you'd think people accusing canon of crippling or doing things on purpose to prevent sales would also spend two brain synapses on knowing what the heck they are talking about.
the XC15 basically has the stripped down core guts of the C300 II in it.
It can't use DPAF because it uses a sony sensor :
Whatever it's price sub 2500 or so, it's still the cheapest broadcast compliant camcorder out there with professional codecs that punch out that 4:2:2 300mbps at h.264 4K.
That's what you are paying for.