wrote:

So I'd need 350 feet of 3/4 inch copper tubing to match the thermal
transfer of 1100 feet of Nick's True Value special...

No. Please read this carefully, for the third time: the water films
dominate the series thermal resistance. The thin pipe wall material
makes little difference. Ferguson sells 1/2"x400' rolls of 125 psi
ENDOT HDPE pipe for $48, and the outside water film conductance of
1/2" pipe is higher than 3/4" pipe, per square foot.

Nick, again repeating obvious truths to people who will not listen.