Digital tape editing
Digital tape recorders do not allow cut-and-splice editing, like analog tape does.
With experience, cut-and-splice editing is easy and accurate for stereo and multitrack analog tapes.
The Sony DASH multitrack digital tape recording system does in theory allow cut-and-splice editing, but it is generally not considered sufficiently reliable.
Digital tape recording systems such as DASH, DTRS and ADAT can be edited by copying the tape.
Using a specialized controller, you can copy a segment of audio from one machine to another. Then you can set an 'offset' between the two machines so that when the record machine comes to the end of your first segment, the other machine is just about to start playing the next segment of audio you want to edit on. You can set the punch-in to record to occur automatically.
This sounds complicated, but is surprisingly easy in practice. This is the way all video tapes are edited.
Disk recording systems however offer very much more flexible editing.