Perhaps there are different dynamics in play between a limited and open gun. I have 2 CZ TSO's in .40 that have more than 10K rounds through each them and haven't experienced any issues with either the barrel or frames cracking. Slide stop yes, each has broken 1-2 during this time.
It could be that FTP is referring to the early barrel design of the CM, TS and perhaps TSO, where the 'peanunt' portion of the barrel was less robust. These barrels were known to break at this spot. I have not heard mention after the barrel redesign of barrels breaking on this pistols.