Surely the director had some input in the interpretation of that scene too? Can't have been just SH decision how to play it 
I have been a huge fan of Poldark since I watched the first series and read all the books as a girl. Love the new adaptation but the writing is not great, it's too fast, at times a bit too pantomime and D and R don't have much chemistry. Outlander has totally spoiled it.
I binge watche Outlander S1 early last year after a couple of people mentioned it. Few episodes a day and I was hooked. Was delighted that S2 started almost immediately but hate waiting a week for the next episode. Then I binge read all of the books over the summer 2016.
It's been interesting watching S1 and about half of S2 blind, then now watching events I've read in the books and meeting new characters I already "know". I'm really impressed, actually, at how well the to writers adapt the books, staying true to the texts but taking out unnecessary stuff. I really like the casting on the whole.
I've stopped recommending it to people because it's a bit love it/hate it and when you describe it it sounds wacky. DH can't get his head round the Time travel but can take Got
and I'm too prudish to watch the sex with anyone anyway.