And I never did need one but i'm sure at least most of the fliers that had them also had preflights that were something less than they were before the parachutes.
I very much doubt it.* Every twin-engine and four-engine airplane pilot I know does as thorough a preflight with two or four engines as they do with one.* Same with boat engines.* I check our two engines as carefully as I did when we chartered a boat with one engine, or when we run a narrowboat in the UK with one engine or when we use our Arima that has one main engine.
No one wants an emergency even if they have the means to deal with it.* I don't want to come home on one engine in the GB even though we have two.* We've had to do it three times in the past 12 years and it's not a fun proposition.* I don't know any twin-engine boat operator who says or acts as though having two is justification for poorer maintenance or less-thorough inspections.
We don't double the oil change intervals or skimp on changing filters or injection pump oil or inspecting belts and hoses on our boat because we have two engines.* We do everything we'd do if we only had one engine--- we just do it twice.* I have never said to myself, "I won't make that check (or I'll let that go awhile longer) because we have a second engine."