Question about grid - 12 columns gutter widths

I'm a bit confused on the best way to set up a magazine grid, 8.5"x11" page spreads. I found a great template with 12 columns from http://ift.tt/pgNluf and the gutters are all 1p0. However, this article from Typophile, http://ift.tt/qVlTsy suggests using 5mm gutters between columns of text, which is about 1.1811 picas.

Not sure what to do - having a 12-column grid is very flexible in that you can easily use it to align 2, 3 or 4 columns of text on a page, but the 1p0 gutter seems a bit narrow for columns of text. What's the best practice for using 12-column grids and setting up gutter values? Thanks.