CAB or ? define stable lobe, please?
A unstable lobe can and some will cause valve float from 4800 RPM and above,
Some lobe designs do it later than other do
If your motor is eating up the top of the valve stems needing constant valve adjustments or wearing out the valve springs, keepers and retainer you more than likely have unstable camshaft
IHTHs
Most motor problems will talk to you , under standing what they are saying sometimes is the hard part