I guess I am too old for this group. 14075 for as long as I have been a ham was the calling frequency for RTTY. But every CW contest had the CW contesters all the way up to and over 14100. Those with Beacons on 14100 jumped up and down mad about it.
Then along came Amtor(the first weak signal mode) and I ran a mailbox on 14080(1982). The RTTY shared the band with Amtor up to 14099. RTTY calling frequency slowly moved up the band to 14080 and now 14085(or wherever you like).
Clover and Hellschreiber followed with...a few more. They gathered under 14070 to 14065. Pactor wasn't a big issue for me. All shared the band.
Here comes PSK series. The weak signal modes. FT's et al. It is all due to progress. AM became SSB then Digital etc. RTTY mechanical became Digital...
I may be off a little on dates and missed some digital modes.
So I never know where the FT4 frequencies are. I remember too many de facto frequencies...