Classic pet exp

[Dweed]

Same question as some others here. What happens when you combine 2+ pet classes in 1 group, some claim being in any group removes this restriction? Is this true?

Will the "players" have to deal 51%+ dmg by themselves, or will they only have to out dmg the highest dmg dealing pet? (example: both pets deal 30% individually and players combined do 40%)

Also, what happens when dmg shields are involved? We all know dmg shields are aggro-less dmg. So if you're soloing with a DS and pet, if the DS deals 20% of the hp, would you then only need to deal 41% to out dmg the pet for full exp?
(ds20%+pet39%+player41%)=100% exp?

Thanks for any answers, just trying to get it straight.