Join Date: Sep 2007
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Great points, folks.
The physics and mechanical engineering involved in arriving at a definitive answer are obviously beyond what any of us have covered here.
The bottom line is that I would tend to trust the recommendations of a reputable manufacturer like Harken when it comes to selcting block sizes. I'd bet that they've done the research, run the numbers , and added a safety factor to their calculations before making any such recommendation.