this is funny

[dr. d]

my point is it's easier with a typewriter, you type directly on the boxes, with a printer, it's hard to estimate the margins.

of course it's easy to correct with a typewriter. assuming one has the typewriter with the correct character font and size.
some of our older LTO documents have obvious corrections on them, done by the LTO personnel themselves. they make no effort to conceal the corrections.
but if one's objective is to "change something that must not be changed", then concealment of the act becomes very difficult.

if one is on the dark side,
computer print-outs may be manipulated, and if done skillfully, the xerox of the manipulated document may show only very subtle clues of the manipulation. something an expert-level investigator would pick up, because he was looking for it in the first place.
of course the computer still has the original un-edited document in its files, in case someone investigates.

but if one is in the right,
and the computer print-out is defective,
just have the error corrected by authority and have the printer cough out the corrected copy.
that's what computers are for.