I agree it’s workable, but it’s a bit of a hack. Commercial formal verification software for RTL has this built-in, and once you have 10+ people updating a spec, you need an automated way of checking for accidental constraints.
A mistake that could be automatically checked is specifying a system that is equivalent to FALSE (and so implies anything). I hope TLC adds a feature that allows you to check if your system implies FALSE. In the meantime, checking the invariant ¬Init has the same effect.