I never even thought of attempting a downwind turn to land until I got a check out at KTMH where the only possible efto landing was in the bay. I was given a engine failure and told to turn around - the month before an efto landing in the bay ended with two drowned.
Admittedly, we had got to 500ft and the turn was almost aerobatic steep turn nose down but it was more than possible and even if a hard rapid landing resulted if it was under control it would be survivable.
The point here is that you can practice this a height and in safety. There are places like this and EGHI for example where there is nowhere to go on 20 and the ability to carry it out safely and to know at what height you can do it from is worth knowing.
Its not something a rookie should try but as skill builds it could save your life - but baldly executed will kill you