On Friday in an HTC EVO 3D Ice Cream Sandwich kernel discussion thread, Chad Goodman of AnthraX custom kernel fame wrote that even an HTCDev-unlocked phone in the One series (which the HTC EVO 4G LTE is), is locked from flashing a new boot.img.
If this is correct, this means no custom kernels can be flashed on the HTCDev-unlocked EVO 4G LTE and means ROMs that require custom kernels could be unusable. This potentially would affect anyone wanting a pure-AOSP, CyanogenMod, or MIUI-based ROM on their EVO 4G LTE, as they generally require their own kernels to run.
It would definitely affect anyone wishing to gain the performance and battery enhancements most custom kernels provide.
While I don't have any more to go on than Chad's post at the moment, if true it makes one wonder about HTC's commitment to unlocked phones. It also raises the questions that if they're disallowing third party kernels, is this just another way to slip a CIQ-like program where it can't be seen by anyone, or just a failure to commit to a promise?
While HTC has worked hard to prevent S-OFF from being obtained, at least the case could be made that the only thing that could not be done with an S-ON phone was upgrade radios without reverting to stock. There's no reason for not allowing a kernel change.
Let's hope that an unwritable kernel is not the case on release day. It would be extremely sad to see the EVO open-root line end with such a nice piece of equipment, or going back to waiting for months for someone to figure out S-OFF only to have it patched again weeks later.