Agreed on the quality of IBM keyboards. Minor correction: 3270 technology used coax cables. And the CP command is "IPL" (Re-IPL is used as a verb).
And yup, it wouldn't take long to get back into the swing of old friends like EDGAR again (Edit Data Graphically And Recursively!). One little-remembered VM CP command was DIAL which was used in place of LOGON to put the terminal under control of a guest OS (eg ACP, Airline Control Program).
-Grayhaired VM/370 systems programmer
(Systems programmers write code, in BAL, that runs in privileged mode. I'm not a friggin 'admin' and I don't have to login as root. Don't call me admin or I'll delete your A-disk.)