I'd say you're on the right track w/ the whipping twine to meet your stated needs - "general outdoor use" (i.e. knots & lashings for shelter building, repairs, improvised tools, etc.). The commercial fishing twine seems worth a look & of course no 'survival' discussion on cordage would be complete w/o mentioning mil-spec para-cord. It can be stripped down into its constituent parts (sheath/7 core strings/3threads) for a huge range of applications. I usually carry ~10m of para cord and the same or more of small, flatter braided (not twisted) nylon cord w/ a breaking strength of 40-50 kg.
The climbing accessory cord is definitely tough stuff, but too expensive & less versatile for my needs in general outdoor chores.
"How does this twine compare with the rawhide cord used in sewing leather clothing as worn by frontiersmen."
If you mean modern 'rawhide boot lace' material (which is tanned), this I would tend to avoid in favor of the previous choices as being much weaker per diameter, less durable & weather-proof. Real rawhide does have the advantage of shrinking tightly into a hard permanent lashing when applied wet - if you're after wilderness expedients & capable of taking game, it can be worthwhile.
Regards, Dudley Driscoll
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