golfrewind.com

Is it the torque of a shaft that makes it feel either stiff like a board or flexible even though the 2 shafts are the same flex?

In general, lower torque shafts will 'feel' more stiff than those with higher torque. But remember, neither torque measurements nor flex letter assignment are standardized and so it is possible that one stiff will feel more so than another because, well, it is...as far as butt frequencies go. Shaft profiling will reveal that shafts with a lower tip frequency will play and feel softer as well.