Can you explain why he should stay away from an oil with a 0W winter rating? And why 10F? The difference in pumping and crankability between a 5W and a 0W rated oil isn't seen until you are at -30 or so, at 10F there is zero difference. And it's not "5W base oil".Stay away from 0w unless it is below 10 deg F at morning start ups regularly, like canada or something.
0w-40 is using black magic to pretend its thick enough for a turbo. Cap says 5w base oil, don't go 0w unless its artic temps.
The only "black magic" in that oil are the multiple stringent manufacturer approvals the oil has which demonstrate it's superior performance. But still I'd like to hear why it should be avoided.