Structural metaphors

Fish out of water
people interpret this one as "being a misfit," but actually it's about being thrust into a new environment you're not used to, or equipped for

Bracing
neck braces and whatnot are important but also potentially damaging, because while they prevent dangerous movement while worn, they weaken muscles and make it more likely you'll hurt yourself in the future (unless you also do PT)… they're self-fulfilling prophecies, and a vicious cycle

Training wheels
the thing that lets you get a taste of the thing you're not able to do on your own yet; not as satisfying a metaphor as the others because it doesn't actively disempower you; the stick-and-carrot societal structure isn't like training wheels because it's not just a beginner's step, it's forever

Gutter guards, guard rails
things that stop you from experiencing the worst outcome (theoretically) — in bowling and driving, walking; same as training wheels, but fixed to the environment and not your vehicle

Scaffolding
the thing that enables you to build upwards, a preliminary structure that begets permanent structures; a good metaphor

Quicksand
keep coming back to this one, because the evocative power is just so good…

Factory
perhaps a metaphor for regular, pre-JFS life: everything is regimented, ordered, overseen, and rewarded or punished; factory workers generally don't have much personal leeway