The K1/K2 taxonomy is… not great, precisely because MK-4 and MK-7 can work quite differently. There are also forms of K not falling into either category, because microbes love to partitially hydrogenate the chain leaving you weird in-betweens.
Also doesn't help education of the public due to all the weird forms. It isn't as bad as how the B complex works; a bunch of different vitamins who keep appearing next to each other in numerous reactions.
The damage is still true though. Natural != good, especially when you screw with doses.
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Oh, B. When all the other subscripts are for Vitamers, there's this one guy that just wants to be different. It's not like we don't have enough letters! Having some similarities does not justify this terrible nomenclature!