The editor comes in very hand for some things like search and replace. For instance, say you've got a bunch of loads in the FX direction and for whatever reason you want to change them to FZ. Just search and replace. Another thing I do a lot is comment out portions of the code to do what-if scenarios or just save run time for things I'm not currently interested in or whatever.
And then there is developing spreadsheets or programs that compute loads on members. All you have to do is have it write in a format that STAAD understands then copy and paste it into the text editor.
I understand that taking something as old fashioned as a text editor and marrying to a slick new interface can have it's problems, but there are many advantages to the editor. If you are not going to retain it I hope you can figure out a way to keep the advantages I've mentioned here.