There is not enough discussion about team aspects of goalie success.
Who seemed greater due to awesome dmen and/or coaching? (e.g., Would Dryden have been a HHOFer in Washington? Brodeur in Florida?)
Who was great despite a lack of dmen and coaching excellence? (e.g., Guy Hebert in Anaheim maybe or...)
This is a forever time "unknown". Calls for major massive speculation. Youd have to know what kind of personality the goalie in question had. Was he a "take charge" type? A natural leader? Did he totally instill confidence & quiet in his teammates to the point that they believed were World Beaters no matter what? What style does he play? Technical? Reactive? Truculent & aggressive? Does he communicate? Does he pay attention to Coaching instructions & understand what the Defencemen & Forwards are supposed to be doing & then on the ice ORDER his players to execute precisely that when locked in Defensively?. Is he consistent? Can he skate, play the puck properly involved in transition from Defence to rush? Does he have "vision"?. Mentally tough? Shake off goals or meltdown?. Does he thrive under pressure? 35-40-50 shots a game or does he crater and at what point?
Adding, contributing factors.... did you have weak Coaching, dysfunctional Management & or Ownership that was forever playing head games with their players which affected performance.... inability to close the deal, lack of killer instinct, system or just wide open roll the lines Pond Hockey & so on (?). Just so many variables..... Of all the Goalies Ive watched & studied including psychological make-up, full top to bottom inside out who regardless of whether they played for bottom feeders or teams highly disciplined & or just stacked stood out to me.... and not enough inf on pre WW2 Goalies to speak with much authority as what would be required to fully dissect such a thesis on an individual basis..... I'd be going with guys like Frankie Brimsek, Harry Lumley, Bill Durnan, Terry Sawchuk, Jacques Plante, Lorne Worsley, Glenn Hall, Johnny Bower, Eddie Johnston, Roger Crozier, Ed Giacomin, Bernie Parent, Billy Smith, Grant Fuhr, Andy Moog, Eddie Belfour, Patrick Roy, Kirk McLean, Curtis Joseph & Martin Brodeur & those are just the obvious ones to anyone who's played the position at an appreciable level & studied it very VERY closely.
As for Dryden.... no. I dont see him having much of a career if he winds up in Washington or any club playing below .500 hockey. I dont see Hasek excelling in such conditions at all, as in none whatsoever. What I also see are a number of guys who back in the day, 6 NHL team era never really got the chance to show what they could do and who were absolutely top tier NHL caliber but with only 6 openings..... then when they mandated the 2 dressed, so what? Who the Hell wants to go from Starter in high level Minors to Backup in the NHL? If you have the kind of PRIDE required to be that good, no thanks. Stay in the Minors. Work ethic, pride, attitude, thats huge. Not some second string fiddle to anyone. Eff that. So ya, all kinds of guys who gutted it out in the minors in the late 40's through the 60's. All levels. USHL, EHL, WHL, QSHL, AHL, IHL etc. And if you really wanna know the position, best be boning up on quite a number of them as well. Guys who I absolutely add to those Ive mentioned above who if given the opportunity to string together Starts.... handled properly. Roberto Luongo wouldve likely made my list but he was mishandled which I felt did affect his confidence at times so some inconsistencies.... I also didnt like his lack of aggression. "Too nice".... gotta take the edge of your Blocker to the mouths of Crease Sitters, chop the ****er down, make room for yourself, keep those Shooting Lanes open. You cant see the puck your screwed....
Just a myriad, wide range of tangibles, intangibles to consider, dissect, and as I said, calls for speculation.... For example.... Ive got Sawchuk in there right? Yet he cratered in Boston. Thats not good. Real bad. So, lets shave that list down even further yes?.... and youd'd be lookin at a far shorter list.... Brimsek, Durnan, Plante, Worsley, Giacomin, Smith, Fuhr, Moog, Belfour, Roy & Brodeur in terms of actual Stanley Cup Winners EXCLUDING Giacomin..... Seriously complicated ????? What about Vachon & Vernon? Cup Winners.... Maniago? Meloche? Bruce Gamble? On & on. Ive seen, studied them all. Guys in there who were for periods every bit as good as Plante, Fuhr etc just in bad situations, whatever...