Plumtree named a recognised eighthman on the flank and a flank at eighthman in last weeks' clash against Zebre. The latter was none other than Springbok and Sharks captain Siya Kolisi, with another leader in Phepsi Buthelezi also playing outside of his usual position.
But that's the nature of combinations. It's not always about the best player in his position, or whether he is playing in his best position, but also how one player contributes his strengths to the loose forward trio.
Talking about the loose forward combination, Plumtree explained that, "I like that loose forward combination, I like how their skillsets complement one another.
"Particularly on attack. All three can jump in the lineout, all three are good defenders and they're tough, rugged rugby players. I love that combination."
Plumtree added that playing a recognised six at eight and an eight at six is also about developing players' versatility.
"I'd like to develop Phepsi as a six more, Siya plays at six for the Springboks, but I like him at eight because of the skillset he brings on attack," he continued.
"He has quick hands and some lovely offloading skills which I like in a number eight. A six is more of a competitive position where you're harder on the ball, a position I'd like to see Phepsi get better at.
"Phepsi is also a tough runner, we've seen that throughout the season and I've been encouraging him to have a real work-rate where he has a large influence on the game.
"Phepsi has probably been our stand-out forward this season so far, playing really consistent rugby."
Plumtree also raised the point about competition for places, because players can never rest on their laurels in the drive for success.
"And then not forgetting guys like James Venter, Manu Tshituka, Nick Hatton and Tino Mavasere in that space as well, seven loose forwards I have a lot of time for," he said.
"They [the incumbents] will have to play well because there are four other guys pushing. We have some really nice competition for those jerseys."