While I do agree with the latter, it should not hurt the gar, I have to TOTALLY disagree with the former!
I have with every gar (LNG and Florida, and the prohibitive extreme vast majority of every other fish species) seen an undeniable EXTREME preference for FRESH food! Seriously, experiment and put a fresh batch with a past prime batch of fish and see if your fish DO NOT select the fresh (as if by magic!).
The true gar may be the worst (or best depending upon you perspective) at rejecting older food. The nostrils on true gar are at the end of the long snout a greater distance from the mouth than most other species of fish. They also hunt in stealth mode rather than quick strike swallow method.
This gives gar a far better chance to determine the relative "freshness" of its prey and either disregard or release from it's jaws before entering it's mouth.
I have dozens of times seen (and never once not seen) a gar refuse to eat a dead fish that it killed itself earlier. It knows it escaped it 10 minutes prior and is now dead from the struggle, but it's dead now and not "fresh" enough to eat!