who says it is "usually" 70mm/s??
Speed depends a lot on the machine it will be run on as well...
As an example, I can run PLA+ on my FT-5 at 100mm/s, but only the SD4s only run at about 40mm/s - two very different machines with very different speed limitations, same exact material... needless to say, on the FT-5, i have to run the material a fair bit hotter than I do on the SD4.
So base you temp tower on the speed you will be using the material at the most. If your primary usage is going to be the lithographs, then do the temp test at that speed
SD4 #1 & #2 - Lawsy carriages, E3D v6, Rumba controller board, mirror bed plate, X motor fan, upgraded PSU & Mica bed heater
SD4 #3 - in the works ~ Folgertech FT-5, rev 1
Printit Industries Beta Tester - Horizon H1