How the hell do you forget to pass the puck? That takes no physical strength.
I am by no means going to defend Richards, but uh, what? He didn't just "forget"... Comments like these just scream out that the poster either has never played the game or, if so, somehow lacks a basic hockey knowledge/understanding of what it takes to play. The first thing I'll say is that he hasn't just "forgotten." The second is that the physical strength of a player - in terms of just being in shape for the season - impacts the cerebral/skill aspects of the game more than people may realize.
A lot of the more fundamental parts of the sport don't necessarily require "physical strength" - like passing, stickhandling, positioning - but are things that can be pretty heavily impacted by an extended period of time off. They are parts of the game that - especially to play at a high level - you need to be in "game shape" to execute properly. By "game shape," I mean that they all come instinctively; you aren't taking the extra half second to think about what you're doing; you are able to see the ice, react quickly and make smart decisions; and need to have your timing synced with the pace of the game. Many of those things are like riding a bike, in that you don't truly "forget" how to do them -- but they are all things that can be thrown off if you haven't played a game in months or are second guessing yourself (practices don't count; no matter how hard the coach may try to make them resemble a game scenario, they simply won't be the same pace as a game or involve as many moving pieces). And any of those things being thrown off just a little bit can mean big problems at the NHL level.
So I don't think to characterize his failures in these areas as "forgetting" is really very accurate... It isn't like he just "forgot" these skills and they will never come back -- it has to do with his failure to be prepared for the season, which has been compounded either by becoming a mental-case during his slump, a lack of heart, effort, motivation, or some combination. This is abundantly clear at this point.
Richards didn't play any games during the lockout, just sat on his butt on vacation. Of course he's going to be a few steps behind a lot of the guys who did - this was foreseeable; too bad not by Richie himself... He started the first half of last season slowly as well (if this becomes a theme, color me unimpressed with his dedication in the offseason). He did end up turning it around somewhat - so I'm not writing him off yet. But that said, it's been 31 games. Dude needs to figure his **** out at some point. Obviously, we all would have hoped Richards would have gotten it together by now - he's had plenty of games to get back in game shape. But at this point I'm seeing his issues stemming from more than just his timing and hockey sense being off... he's slower, lacking the physical strength to get into areas of the ice he needs to be able to get (and no I'm not necessarily just talking about board work), and not showing the kind of effort or heart that you'd like to see out of a guy being paid $6.7 mil per year and who is wearing an 'A'. If he is too slow on his skates to keep up with the pace of the game, his passing, puck possession, and positioning will inherently suffer. The same goes for if he isn't strong on the puck. Those things are 100 % on him.
From a playmaking center like Richards, if you are both physically out of shape and haven't gotten your mental game/timing back yet, that spells disaster. And that is what we're seeing.
To try to get this back on topic... with how this relates to Nash...
If you have Richie and Gabby sucking, a black hole of a bottom 6, and a defense that can't consistently produce offense, the opposing team's defense needs to shutdown a total of 4 forwards (really only one line). That is not exactly going to stretch even the worst teams' defenses, and means Nash becomes the focus like he was on CBJ. Despite this, I think he's done a very good job for us this year.
