May I ask what Pronger would need to have done in 2006 for you to have seen that playoff on the same level of 2000 Stevens and 2015 Keith? Pronger was his team's leading scorer (neither Keith nor Stevens were), he had double the plus-minus of his next teammate, he was the best player in an upset of a 58-win team, and by the next season, Edmonton was out of the playoffs while Pronger was winning the Stanley Cup with the same team he dominated in the 2006 playoffs: Anaheim. Pronger is the catalyst in three cities of success; Keith is one of the heads on Chicago's Cerberus.
And I wasn't suggesting that Pronger has three runs better than 2015 Keith, but instead that Pronger's three runs as a whole would be better than the best three of any remaining eligible player. And on top of that, he has five more playoff runs at/above 0.75 points-per-game. The only defensemen who have hit that somewhat arbitrary threshold in more playoff runs than Chris Pronger (8) are 1980s players. With respect to Stevens - who I also have very high this round - he wasn't the offensive player in his Finals runs the way Pronger was in his teams', and in terms of defensive performance, they're comparable enough to where Pronger's offensive edge should place him above in terms of their very top runs.
Rounds Team Was Upset
Chris Pronger
2000: 7 GP, 3-4-7, +0, 2 GWGs
2008: 6 GP, 2-3-5, -1, 1 GWG
2011: 1 GP, 0-0-0, -3
Duncan Keith
2012: 6 GP, 0-1-1, +1
2014: 7 GP, 2-1-3, +2, 1 GWG
2017: 4 GP, 0-1-1, -6
Scott Stevens
1985: 5 GP, 0-1-1, -4
1986: 6 GP, 1-4-5, +4
1987: 7 GP, 0-5-5, +4
1988: 7 GP, 1-6-7, +0
1989: 6 GP, 1-4-5, -2
1991: 6 GP, 0-2-2, +1
1997: 5 GP, 0-1-1, -2
1998: 6 GP, 1-0-1, +4
1999: 7 GP, 2-1-3, -2
2002: 6 GP, 0-0-0, +5
Worth noting that while Stevens' teams were upset more often than Pronger's (and Keith's thus far, obviously), like Pronger, Stevens often looked better in defeat than one might expect.