Review the tarp market....
Many low end, entry level or in expensive poly tarps use grommets....
Almost every specialty manufacturer, upper end level, UL tarp maker ( save one?) uses GG, or GG and D rings or, or light weight webbing.
Lot of experiance here....Wonder why they take this approach?
Are you trying to use a go cart approach to achieve a race car product?
GG loops are easily sized and positioned to accept hiking poles at the ridge tie outs, or any other point for that matter.
Recommend giving up on adding layers,weight and spending time on the grommet approach....just my 0.02.
Ounces to Grams.
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