If the purpose is a faster meal down the road it does defeat the purpose somewhat.
If the purpose is to save a wonderful meal item with no noticeable difference in quality that will take little trouble later than it doesn't.
3 times I have had guests cancel after the meat was in the water a while. I refroze their portions and all I had to do was plop them in the water for a while when I was in the mood and if anything they were better.
Probably I wouldn't precook food sous vide to reheat later unless the cooking time was long, but if it is already done I would refreeze it. Basically you can't lose by trying it. Something cooked for 24 hours does not take 24 hours to reheat.
Sous vide food is supposed to keep longer in the fridge as well.
And about safety. There are companies selling sous vide meats. I have not seem any or I would buy one just to see. Apparently you can defrost/reheat it using any safe method.
I personally have no problem with leaving it in the bath for an hour or two unless I am really hungry and then I will just make a sandwich