This item is from the Yet Another Enhanced IDE/Fast-ATA/ATA-2 FAQ, by John Wehman and Peter den Haan with numerous contributions by others. (v1.92).
It should be, but there are problematic cases.
It has been observed that some controllers will base their I/O cycle times on the bus clock of the computer. This means that with a 50MHz bus, the cycle time will be faster than with a 33MHz bus. This could lead to undesirable results if these cycle times are faster than the drive can handle. Make sure your controller supports multiple bus speeds in the software setup, and if necessary program it correctly.