are post probe pci cards of importance to a h/w technician.shud a h/w technician be equipped with one

A POST card is nice to have, although not an absolute requirement. The requirement is knowing how to troubleshoot it to begin with, but a POST card can make it easier to determine if a board is dead and can locate problems that are very difficult if not impossible for a technician to diagnose.

Yes, a POST card is very nice to have, but not mandatory and certainly does not replace some good solid learnin' in the old noggin. That's your best troubleshooting tool by far.