Never would have guessed that, MrAtoz! (“Interesting nomenclature” :D)
Cracked my infallible code, did you? 
I always assumed that titles were only remembered by the most geeky of people, and that most shows just didn’t have that devoted type of following. Or, if they did, no one was catering to them. I think your show has to have a separate fandom for the shiboleth of knowing episode titles to be useful.
Until the Internet, that is, where titles are easy to find, and help you communicate since it gives people something to look up if they want to know more. They’re much more natural than referring to season:episode form.
I mean, I didn’t speak Trek titles until the Internet, that’s for sure. And I don’t think I’m that unusual.
Homicide: Life on the Street had titles that were horrible puns at the expense of tragic characters. You’d feel dirty just knowing about them. Other shows, like Friends and NCIS, had titles where major plot points were revealed. If they combined episodes, it might be like “The One Where Caitlin Gets Her Head Blown Off at the End” or “The One where Jenny’s Gonna Need a Closed Casket Funeral.”
Having grown up in the '70s and '80s, it’s true that we didn’t talk about TV in the way we do now. Even those of us geeky kids who endlessly discussed Star Trek, we didn’t use the episode titles and they were on screen.
It was certainly not part of mainstream adult culture to discuss TV show episodes in such detail as to require knowledge of episode titles.
BTW Sesame Street had a four-digit number at the beginning of each episode, probably a serial number of the episode. (Don’t know if they still do that, or why they did. My dad thought maybe it was for teachers who wanted to show it to a class or something.)