I had one back in the day that was rated stiff and did indeed play a bit stiffer than most if not all others I tried in that flex. Having said that, I don't know if it was overall stiff, or just tip stiff as both gave the same result for me. I was doing a lot of fun experimentation at the time and learned that my swing doesn't agree with shafts made for aggressive tempos.
Add this to the recent mention of the Harmon CTB shaft (my favorite back then) and you do have me feeling nostalgic. LowPro''s site was like a candy store to me back then.