I understand your concerns and there's always a good chance that Rask loses a few games in a row and Thomas wins a few in a row.
But what exactly do you mean you can't stomach the thought of Rask only playing 50 games?? Does that mean you're just nervous it's going to happen or your on the fringe of winning a title and your team simply can't afford it??? What's the level of confidence you have in either of these things happening?
I just feel that it hinges on more things than Rask continuing to play at his ability (that 77% efficiency is awesome).
1. Thomas has to get some games early and take advantage right away.
2. Rask is going to be the starter on opening night - he has to lose faith in coaching staff.
3. Boston would need to be comfortably in a playoff position or divsional seed in order to give Thomas any "freebie" games. By that I mean games that may be on back-to-back nights or against non-playoff teams. Any start out of the ordinary.
4. Rust is a factor for Thomas. We have seen how he can struggle when not getting all the minutes.
Those are just four of the main ones. And of course I do realize there are many reasons why Thomas could just as easily steal games from Rask ... or have them fall into his lap.
But if you want to know which is more likely to happen, clearly Rask has all the ability and skill and toughness needed to succeed and play at least 60 games.
.....
If you ask me, between Lehtonen who we all know comes with a giant risk, Quick who could be losing starts to Bernier at any given moment and then Rask...it's pretty easy to have confidence in keeping Rask.
That's the issue with Quick ... it's not that I think he'll play any worse than last season ... I just don't see HIM getting the games. It might come down to salary cap issues as well, who knows. Anything could happen in the next few months but there's no way the Kings keep Bernier in the AHL for a full season.
Basically, in your situation, something's got to give. Either Lehtonen will get injured (probable probable), Quick loses a ton of starts to Bernier (more probable) or Rask stinks up the joint for many portions of the season and Thomas gets 30+ games (less probable).
You need to answer for yourself which one you think happens first and second.