If the limit screws are adjusted correctly and you don't ever screw with them (no pun intended), then the dd isn't needed. Unfortunately many newbies think those screws are some kind of an adjustment for fine tuning the shifting.
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The Lord is merciful and gracious, slow to anger and abounding in steadfast love. - Psalm 103:8
I am a cyclist. I am not the fastest or the fittest. But I will get to where I'm going with a smile on my face.