i like to use it,, I think it gets the wood used to bending,,,
especially if the bow is reflexed,, I will put the bow on long string before bracing,,,even when it has been braced before
I really think it helps when making a heavy bow,, on lighter bows I can see you could skip,,
and I think it is real help with sinew bows,, really hard to tell what they are going to do first time braced
the long string gives you a hint
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I think it helps increase the odds of not breaking a bow on first brace