For standard levels of indentation, I get that tabs may be useful, but in /etc/fstab, I absolutely hate them – how many do you put if the individual elements vary in size? Always just one, resulting in e.g.

    this_is_a_long_line<tab>defaults<tab>…
    short<tab>defaults<tab>…

with the following elements not aligning? Or however many are necessary to get things to align, which sort of destroys the semantic meaning?