Grids and padding/margin

[debugwand]

Given that if you add padding or margins to elements also form a grid and together add up to 100% (e.g. 3 elements that are .size1of3), your layout will collapse (until such time as we can forget about IE<8 and use box-sizing), is it worthwhile to enforce 0 padding and margin the following to .unit and .unit-right in oocss / core / grid / grids.css?

.unit, .unit-right {
  padding: 0 !important;
  margin: 0 !important;
}

[ghost]

I saw that www.box.net uses border-box. How does it work with older browsers?