Lemme tell you guys something about the ACU...

Ever looked at 2 soldiers, one wearing BDUs and the other ACUs, at night? The guy in ACUs positively glows, and the guy in BDUs completely disappears.

The principle behind the ACU universal pattern was this:

Standing against a green background, the wearer would look more green.
Against a tan background, the wearer would look more tan.
And against a grey background (i.e. buildings), appear more grey.

However, the way it actually works is thus:

Against a green background, the user appears more Tan,
Against a tan background, the user appears Green,
and against a grey background, the user actually appears blue-ish (no joke) at certain times of the day, and otherwise appears very very tan.

Bottom line, the ACU doesn't do what it is supposed to do. the principal behind it was sound, but the execution was wrong.

It is also the shortest lived camouflage uniform ever to see general issue, I believe. See what happens when palms get greased? <img src="/ubbthreads/images/graemlins/paperbag.gif" alt="" />