FF doesn't "go bad" if reasonably tended to, so the information from that site is wrong. I've been doing it for 2 yrs now and have never smelled anything but mild fermentation or strong fermentation, but no smell that would denote a "bad" batch as opposed to a batch that was just fermented at different levels.
It's very, very difficult to get fully fermented feed to go "bad"..one would have to neglect it for a long time, without keeping it moist or refreshing it with fresh food(new grain) before the good bacteria would die off in such numbers to let bad bacteria take over.
Don't be afraid of fermented feed..it's not at all risky... and please, don't put too much stock in that site....a good bit of their information is not based on time or experience, just things they've read and repeated. There are big threads on fermented feed on this forum where many, many, many people are fermenting their feed and some have been doing it for years, so their collective experiences with FF is incredibly more accurate.
One is a controlled ferment that converts the proteins and sugars in the grains to amino acids, something the chickens can actually absorb and use, so that the feed doesn't pass through their system undigested to land on your coop floor, there to rot and stink. It can increase the protein absorption by 12%, make your simple feed into a super feed that lets you feed almost half of what you used to feed. Meanwhile, it's populating the chicken's bowels with beneficial bacteria that inhibit the growth of harmful pathogens like coccidia, salmonella, e.coli, etc. It makes the yolks larger, the intestinal villi grow larger(thereby increasing total area of absorption of nutrients), increases laying, improves overall health, improves the appearance and quality of feathers, decreases the smells of the feces while attracting less flies to the coop, the poop breaks down in deep litter more quickly, improves the culture in the coop and soils of the run, renders the feces less "hot" for composting purposes for a quicker turn around to the garden, and cuts down on feed waste merely by wetting the feed and the manner of feeding it in meals instead of continuous feeding.
The other is just wet, moldy feed.
See above. Try fermenting their feed and get the benefit of all the good from it without worrying about feed spoilage when it's merely wet and sitting under a heat lamp.