There is a difference between wearing and using the climbing safety gear. I know of a station owner that banned a group of riggers from their towers because they insisted on climbing the tower without using their safety gear since it was "faster for them to climb" that way. It was their belief that it was only necessary to hook onto the safety line once they go to the work location on the tower. We later learned that one of the banned riggers fell to their death while climbing another tower while not hooked up.
The tower climber may have had all his equipment on, but was it on right. I know I have on occasion incorrectly snapped in, and then when testing it before I actually put any weight on the restraint system have it come undone. Pretty scary feeling, hope the worker recovers.