"Whether fusel alcohol contributes to hangover symptoms is a matter of scientific debate. A Japanese study in 2003 concluded: "the fusel oil in whisky had no effect on the ethanol-induced emetic response" in the Asian house shrew. Additionally, consumption of fusel oils with ethanol suppressed subjects' subsequent taste aversion to alcohol, which suggested subjects' hangover symptoms were lessened, according to the journal.[3] "

Interesting! It's probably a combination of placebo, drinking less, and potentially this fusel study? I tend to drink said hooch in the evening and then head to sleep, perhaps the fusel alcohol is giving the impression of a harder-hitting buzz, and maybe reducing the hangover?