15thc perception on swallowtail merlons?

[Koen G]

Also if all examples of ghibiline merlons in the early 15th century were identified how would we use that knowledge?

I guess it's more of a general resource. Not everybody has a clear idea of where these merlons were found. 
What I hope is that at some point we might be able to compose a map of something else (for example a type of script found in manuscripts) on a different layer, and we might see areas overlap.