Joan Brooker and Nancy Eddo, best known as a comedy team who worked for shows like Full House and Gimme a Break!, lend their comedic efforts here. I haven't seen their writing elsewhere, so I can't judge, but they're definitely not funny here. MacGyver is portrayed as a sap. It's great he likes to help people, but sheesh, when dopes like Penny and Yuri deliberately ignore him as he's standing there saying "Don't go outside," and they go outside... well, some people deserve what they get. MacGyver just lets people walk all over him here with a minimal struggle.
The Penny Parker character has always walked a fine line between charmingly oblivious and downright stupid: here she jumps all the way over to the stupid side and stays there most of the episode. A little of Elya Baskin goes a long way, and it goes way too far here. Only Vincent Schiavelli, as a hitman intrigued with pain and a cool gadget of his own, lends anything resembling class here. His role here is essentially the same as in Buckaroo Banzai and later in Tomorrow Never Dies.
The two MacGyverisms aren't bad (even if the magnesium pipe gag is a lesser version of the one they borrowed from the first season), but them and Vincent Schiavelli are really the only things worth giving a look to here. Even Richard Dean seems to despair at times.