Hypothetical: 12C program editing

[brouhaha]

Suppose a new firmware version for the HP-12C added program editing via new INS and DEL features in program mode, which would insert or delete one program step at the current location.

if the program was already full (99 steps, step 99 not "g GTO 00", and you pressed INS, would you want the calculator to give an error and not change the program, or would you want it to silently delete step 99 ot make room for the new step?