[SpaceBar]

Actually it's not the Lorentz contraction (length foreshortening) of special relativity. That's an artifact observed due to relative motion between event(s) and observer. Gravity waves actually distort the local spacetime metric and curvature it passes through, something independent of any ‘observer’.

[ETL]

Yes, but since gravitational effects are equivalent to acceleration effects it basically works out to the same thing, although I can think at the moment exactly how.