Reason for separating Latin and Cyrillic kerning groups?

I remember reading somewhere that it is best not to combine kerning groups between Latin and other scripts like Cyrillic. Could anyone elaborate on this?

For example, in Latin, you might have a kerning pair for "C" to "o", and in Cyrillic, the Es looks like a Latin "C", and the Cyrillic "o" looks like a Latin "o", meaning it seems much easier to just place them in the group containing the formal Latin equivalent. 

Without combining them, I then have to reference a bunch of Latin kerning pairs to build a similarly kerned Cyrillic alphabet. 

Does that make sense?