Interesting. Connor averages 18:41 per game Even Strength and Leon 17:08. Assuming 50 minutes of 5v5 per game, if they played together every minute that Drai is on even strength, the team would average 1.998 goals per game. If they never played together during the assumed 50 minutes of 5v5 per game, the team would average 1.732 goals per game. For simplicity I've assumed Even Strength and 5v5 as the same, even though I know that isn't accurate, but overall I guess this shows that the Oilers do produce more as a team over the course of a game when they are together.
Would be interesting to see the effects on goals against to see the overall impact towards outscoring.
Interestingly as well if you dig further. RNH w/o McD is 2.48 so he produces better without McD than Leon does (marginally so). Furthermore RNH with McD is 2.54 with isn't even close to Leon with McDavid, and is only marginally better than RNH alone or McD alone.
Perhaps this in the best scenario if one of RNH or Leon must be on McDavid's line.