Lowest possible gathering to 1-shot clear folklore node level 60 1-star items: 645
Lowest possible perception to gather 2 nodes using (DE+MA,DE+MA,DE+MA) for level 60 1-star items: 645

*** Note you would need slightly higher perception in order to do DE+Impulsive,DE+Impulsive,DE+MA.

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As for 95% gathering and 15% HQ rate on 1 star items I'm not sure. I personally have over 700 gathering/perception and I think I'm still only at 89% gathering rate.