Grant Edwards <firstname.lastname@example.org>:
> Definitely. Indenting with tabs vs. spaces is mostly personal
> preference (though spaces are better!). But, mixing the two is right
> out, and should be stomped on hard.
Often one person writes the code and another person fixes bugs in it or
adds features to it. So if one uses tabs and the other refrains from
using them, you'll get the mixed style you abhor.
Even if we accepted that to be bad style, there's nothing on the screen
that would warn against such usage: the lines seemingly align perfectly,
and the code runs as expected.