Shields as Weapons

Personally, I feel that Shield Runes are Shield Runes, and that (even though they CAN be used as weapons) they shouldn’t get Weapons Runes at all. However, within the scope of the universe, unless you get an amalgamated rune you CANNOT gain two benefits from the same rune. Otherwise, as stated many times, why would someone use ANY other weapon?
If not both for simplicity, then this for simplicity.

the crux of the argument to me is when I’m using my shield as a weapon (usually to shield slam or similar) Its a weapon, and not a shield during the recovery time for that maneuver. and then I’m using it as a shield.

when I don’t have use of my shield I don’t have any benefit from it, Runes or avoidance keep that in mind when saying you get the benefit from the shield all of the time.