13pt font at 72dpi is actually a pretty decent body font size, and helvetica renders not altogether horribly with these settings, so it's a reasonable choice for designers testing only on macs.
That said, yes world, please don't use Helvetica for body font, most people don't even have a good version of the font, and plenty of renderers butcher its kerning, anti-aliasing (especially with versions of the font without good hints, or with renderers that ignore them), and even its baseline.
That said, yes world, please don't use Helvetica for body font, most people don't even have a good version of the font, and plenty of renderers butcher its kerning, anti-aliasing (especially with versions of the font without good hints, or with renderers that ignore them), and even its baseline.