With your shield or upon it

I was thinking about shields. Many have commented that the +/-1 bonus to your AC is not enough. Historical reenactors and S.C.A. participants will tell you that getting past a shield is hard. Certainly greater than a 5% difficulty. Roleplaying to me however is about storytelling. Heroic combat isn't about cowering behind a shield. Players of course want every bonus they can get. Its understandable given that the origin of the shield rule probably comes from the wargaming roots of D&D. In order to fit as many different types of armour into just the 11-20 range on a twenty-sided die, shields could be just a bonus of 1. Shields Shall be Splintered! is a cool idea where you can sacrifice the shield to negate damage. But I still want some thing that changes the way shields work without adding any complexity. Taking an idea from Mazes & Minotaurs; wherein a player my roll two dice taking the higher score when using their chosen weapon. The double dice idea can be turned around for use a shield rule. When attacking an opponent who carries a shield the attacker must roll two dice taking the lesser score. Its simple applies at all times and provides a substantial bonus but does not make anyone invulnerable. Eliminating the bonus does leave holes in the AC chart but that makes room for custom armour types.

P.S. -longest ever between postings