In the last log, I talked about the problem of low impedance loads on the programming pins. It turns out that this really only applies to TPID because it's a bi-directional pin, and the chip has a collision detection mechanism. TPIC shouldn't have similar issues. So the simpler solution (as opposed to adding a MOSFET driver) for this is to just swap the optoisolator and button pins. As long as you don't push the button during programming, it won't interfere at all. Having TPIC shared with the optoisolator will cause the LED inside it to blink during programming, but that's not a big deal. To help with this even more, we can actually swap POWER and WARN as well, because WARN can be disconnected much more easily.