He's talking about using a NIJ rated soft armor in place of a trauma pad beneath hard armor plates. You or someone else would have to shoot it to see if it provides any significant increase in protection. When you're talking about improving LVL III hard plates you're talking about wanting to stop .30-06 and up, I don't think an extra layer of soft armor is gonna do that for you, therefore I see little benefit in it.
Edit- and YES, you do need something soft beneath those plates. I wouldn't dispense of them just to shave a few ounces or bucks, as I mentioned earlier if you take a 5.56/7.62x39 round to the plate is going to leave a nasty bruise even with trauma pads. Wouldn't want to know the effects without them.
NCO of Marines, 3rd Award Expert Rifle, 236 KD Range
D Co, 4th CEB, Engineers UP!! OEF 21JUN-20SEP2011
REV. 19:11 And I saw heaven opened, and behold a white horse; and he that sat upon him was called Faithful and True, and in righteousness he doth judge and make war.