Semantics: Hopping electron transfer, or more cofactors?
There is ongoing research regarding which long-range electron transfer mechanism operates in particular systems, hopping (where the electron resides on bridge units) or superexchange (where the electron transfers between donor and acceptor using bridge states, but not "residing" on the bridge discretely). See, e.g., doi://10.1021/jp2054876.
So, is an electron "hopping" along bridge species between what the community agrees are a donor and acceptor different from an electron undergoing a series of direct or superexchange transfers among the community-agreed-upon donor and acceptor PLUS a series of donors and acceptors (bridge species) that we don't think about as such? In other words, is the distinction between hopping and superexchange merely semantic in how we define donors and acceptors?