This is so far the only episode to have the main cast with no "Also Starring" and no "Special Guest Voices".
The way the propane tank explodes is impossible. The propane would have leaked and ignited through the hole Burns made, burning him and Homer instead of propelling the house away. Also, since Burns is so weak, it would be impossible for him to pierce a propane tank with a single blow!
Mr. Burns had fired Lenny in "Burns' Heir". However, Lenny is seen working at the plant in later episodes.