Goalies work on most parts of their game throughout their career. It's why each team has a goaltending coach.
There's actually a pretty interesting article about how Dubnyk changed the way he tracks the puck and it changed his game.
Alright, that sounds awesome.
But seeing has how the 31 year old Howie still has trouble learning the skill of puck-handling, I'm not too optimistic in his ablitity to overhaul/adjust to this system on the fly (if he were in fact to try and learn it, that is)
And of course they work on thing during their career. I remember playing baseball when I was like 11. I wasn't bad to start the year, but after a while I just had the hardest time even making contact with the ball. That threw my confidence down the drain, so every time I went up I already knew I was going to strike out (sure enough, I did!).
Then finally towards the end of the season, whoever's dad that was 'coaching' 3rd base came over to me mid at-bat. "Hey Nate," he says "I just noticed you're taking your eyes off the ball before it even gets to the plate. Make sure to watch the ball all the way to the bat." And I did. And I at least made contact with the ball during that at bat.
All that said, I was 11. Not a professional baseball player who couldn't hit or throw the ball to 1st to save my life. But hey, if Howie works on it and it gets him going, he could be a good player for someone else!