Late to the party... My interpretation is if the attack angle is insufficient to damage the armor it is also insufficient to damage the shields.
Like sloped armor on a tank the angle of the in coming round makes a big difference on whether on not a round can make it though the armor plate. If there were real life shields they would probably work the same.
A near miss is not a direct enough attack to cause the shields to use energy stopping and or absorbing the damage... and instead the shield simply deflects (maybe even letting some of the material bounce off the armor) or refracts it.
There is president for force fields working inside armor... lashunta ringwear is comprised of "Metal guards, woven chain sheets, and force fields stretch between the bands to form a complete set of protective gear" though it provides AC, it does not provide additional tempory health like force field upgrades.
Anyway it is meant to be abstract, with multiple ways to achieve the same results. Maybe it's like Star Trek (giant bubble) Maybe it's like Dune (only the slow blade penetrates) maybe it's like Ironman's armor (forcefield bolstered... which also describes the Lashunta Ringwear)