Look, a movie called Days of Thunder was released roughly contemporaneously with this show, and that's reason enough for the title. Let's not go around asking dumb questions about whether or not it has any actual relevance whatsoever to the episode.
The idea here is that Quackerjack tricks Darkwing into thinking he's going to commit crimes so as to make a fool of him when he tries to stop these nonexistent acts of larceny; then, when his confidence is down, he poses as a psychiatrist and convinces him that the life of a crimefighter is not for him. Then the real crime spree begins, until DW can get his head back on straight.
In the previous entry, I complained that Quackerjack seemed kind of pointless; just a less-distinctive version of Megavolt. This episode is a big improvement, however; it does a good job of making him into a distinct character. For one--though whether this will be a recurring motif, I don't know--he demonstrates an ability to psychologically manipulate DW, which something ability that no other villain has evinced thusfar. Also, he comes across as a genuine psychopath: Megavolt may be crazy and amoral, but you don't get the impression that he's necessarily evil per se, whereas it's possible to imagine Quackerjack murdering you just for teh lulz, probably while making a terrible pun. He's about as scary as a villain on a show like this is likely to be, and if the writers are able to maintain this level of intensity in future appearances, he's definitely one to look out for.
-One of Darkwing's more memorable indignities when the wrestler that he's going up against in a charity match makes him into a balloon-animal giraffe.
-"This is Dan Gander outside First National Bank, where the rubber chicken crisis has just entered its tenth incredibly tedious hour."
-I know this is Disney-world, where really obvious disguises are the norm, but the fact that the psychiatrist's half-red-half-purple face doesn't raise any alarm bells really takes this trope to a new level.