Comrie on grammaticalization, language typology, and reconstruction

¶ … Comrie, Reconstruction, typology and reality

Describe what grammaticalisation means, as this term is used by Comrie.

The best I can make of this -- since this writer never actually defines the term as he uses it -- is a concept that languages have a tendency to become more complex. This complexity in the way words are pronounced or the rules used to understand pronunciation seems to be what the author means by grammaticalisation.

What does Comrie mean by the "realization of the human language potential," as opposed to the development of this potential? (page 250)

It seems that the author is talking about the difference between coming to realize there is the potential to do or learn something and the actual development of whatever that something is. A friend of mine tells the story of first being shown how to knit at the age of 12. She went home and practiced with two sharpened pencils and a ball of ratty string and realized she could do it. A few years later she actually bought proper needles and yarn and a book for constant guidance. She worked at this skill and 45 years later can not only do complex work but can design her own patterns.