[Jim.Cook]

Hi all,please forgive my ignorance but I have only recently discovered that clubs can in fact have a "SPINE".
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4...How important are they to the week-end golfer.

Any info would be grateful..Thanks again.

I tried to answer this question. I made two clubs that had exact characteristics except that the spine one one of them was set at 45 degrees to the target line and the other was set exactly on the target.

I gave the 45 degree one to my pro and asked him to hit a few and give me his opinion of it. I told him nothing else. He noticed it immediately. As he hit each ball he commented "I'm not hitting well today."
I then gave him the other club. Immediately he said "AH, it's not me, it's the club!".
That weekend, I took the two clubs to the driving range and asked as many people as I could to try each club and tell me what they thought. No one commented on the difference in feel. I'll bet there wasn't one person that weekend that had a single digit handicap.
Spining and subsequent flowing takes so little time I do it to every club I make or repair.