They are insanely fast to be little blobs that move maybe once every 48 hours

Frogs' feeding responses are pretty much all instinct. The feeding responses are movement based, so even if you tong feed for the frog's whole life, it probably would learn to take food just running around its cage very quickly. The tongs aren't natural though, so they're what you want to get your frog used to from a young age.

My frog has a narcolepsy-like disorder; once she grabbed onto the tongs then 'passed out'. It took ten minutes to work them out of her mouth. Since then, I make VERY sure to angle them away from her face. If you do that, even if they overshoot the food, their face just bounces off the tongs and they won't bite them. Rubber tips are a good idea.