True enough. But then there are even more ways to spell it wrong, and the general principle still holds. (With a possible exception for cases where you abbreviate a word in such a way as to remove the bits whose spelling differs. But, e.g. “col” is seldom likely to be a good abbreviation for “colo[u]r”, not least because “column” will be a distracting other meaning...)
True enough. But then there are even more ways to spell it wrong, and the general principle still holds. (With a possible exception for cases where you abbreviate a word in such a way as to remove the bits whose spelling differs. But, e.g. “col” is seldom likely to be a good abbreviation for “colo[u]r”, not least because “column” will be a distracting other meaning...)