I had been thinking about something I noticed:

- Byzantines placed archers behind pikemen in a square, suggesting that their archers used indirect shooting:
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- English and Burgundians apparently placed them to the sides of infantry
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- Matthias Corvinus however placed pushkars behind heavy infantry
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Archers beside infantry is reminiscent of pike-and-shot tactics and suggests direct shooting. But how does this fit with Corvinus' placement of pushkars?

I'm not sure you are seeing evolution as much as variation. Archery can be used in different ways within different tactical schemes.

As an example, the system of use wings of archers and a centre of infantry was used by the Byzantines at Taginae in 552, earlier than the Byzantine manual illustrated.