i have a motion pro cable as well and after follwoing a million walkthrough, i still would get clutch pop after a few minutes of using the clutch.
in the MP cable i believe there is about 1cm less of cable compared to outer sheathing, than the OEM cable. the length of the cable itself isnt the issue.
you could have a 6ft cable and it would still work as long as the outer sheathing were sized accordingly to the length of the cable.
when clutch is engaged, the actuator arm isnt fully retreating, and the balls arent all the way in their grooves, hence they have a head start when you start to disengage the clutch and eventually pop out of their grooves.
with an OEM Honda cable, this issue disappears, but for the motion pro cable, the best fix i found was to remove the upper cable locknut.
It is number #25 in this image. this allows for the extra cm of cable to come down into the clutch cover, and drop the actuator arm so that is is fully seated. I also have the adjuster (#21) turned all the way in.
it hasnt popped out since i made this adjustment, hope this helps.