Bumping this just because I unexpectedly got some clarity about taping times. A Facebook friend posted a photo of the 1969 Macy's Thanksgiving Parade, and it just so happens that the photo catches the parade as it's passing the Ed Sullivan Theater, and the marquee is advertising tickets for "What's My Line?" Now granted, it's a different year and a different studio, so it doesn't really solve anything about Curt's mystery for sure, but at the Ed Sullivan Theater in 1969, the tapings were on Wednesday at 10:45 a.m., 1:45 p.m., and 3:30 p.m.
I'm still thinking taping times may have been adjusted to fit Arlene Francis' schedule. According to this 1966 brochure, her show aired on WOR from 1:15 to 2 PM (imagine only being on for 45 minutes a day!):
http://imgur.com/gallery/cHo3VBy 1970, the time slot might have changed. I found a 1980 brochure (
http://imgur.com/gallery/cHo3V) that has her profile, but doesn't mention when her show aired. In any case, it was a short cab ride between the WOR studio at 1440 Broadway and the Sullivan Theater at 1697 Broadway. (It's also possible she could have done the show remotely; apparently that wasn't uncommon for other WOR personalities at the time.)