I have just returned from a local pro shop, I tried a TM RBZ 5 Hybrid in regular shaft there, it's really feel softer than my iron graphite flex R shaft (Taylormade Burner 2007, first version, Asian only I believe)
I hit 8 balls in total, 5 of them shot straight up to the sky and dropped around 170-180 yards, only two are straight, one pull fade, one fade and one push draw... 3 bad hits (topped, thin...)
So, with softer flex shaft, I lost some consistency in ball flight but gain accuracy on where the ball drop. Trajectories are higher, much higher and distance gained are around 30-40 yards.
I was like what the F after the first hit, the ball take off, went straight into the sky with in a perfect straight path and fell hard onto the grass. I then proceed to hit some more and got above results.
I guess with softer shaft, I have more backspin which help the balls take off easier, steep drop angle reflect that, too.
Wow, just wow...