Could "a" be a ligature?

[Rafal]

When you see "a" you can be quite sure "k,t,f,p,d" will not be next, this is not the case for "o"

That's good observation. Now you made me think that "a" and "o" aren't that much similar.

- things like "aiin" or "aiir" are much more common that "oiin" and "oiir"
- but "ar" and "al" (without "i"s ) are the same common as "or" and "ol"
- on the other hand "o" with gallows like "oK", "oT" or "oP" is much more common then "a" with gallows which is rare

By, the way, I just noticed at the page You are not allowed to view links. Register or Login to view. some hybrid of "a" and "n" 
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