Math breakdown: Anime homing missiles
My first job out of college was working for a lab that did stuff for Air Defense. We did stuff like missiles that shot down other missiles for the Navy. Anyway, in my naivety, I asked the more senior engineers why we don't shoot missile plumes. Lots of cheap missiles in the hopes that one hits. (I didn't mention the idea was from watching anime.)They told me that the backfire from the exhaust of one missile might ignite the one behind it if we did stuff like that. That said, I've seen videos of ships firing missiles in relatively quick succession. Just not like the Itano Circus, however.