[Sawrock]

Any system that has stacking buffs heavily favors magic-heavy tropes; why wouldn’t you use magic if it’s another thing you add on? From shield spells in tabletop RPGs being better than using a shield alone to having spellthief hold every buff spell under the sun, it greatly limits character concept. To be the best you need to be more efficient. The same can not be as widely said about magic users using nonmagical means- they aren’t compromising their identity, but are instead clever. Having a thieving sorcerer that can pick pockets doesn’t make him less of a sorcerer, but a magic-using warrior is to the likes of Elric of Melniboné rather than Conan the Barbarian.

If you can only apply the highest buff, it’s still a momentum saver- let’s say you buff your friend. Now he can attack twice instead of wasting a turn on a buff.