[akoboldfrying]

The only pattern I know for sure is that compound words in English tend to begin their lives in hyphenated form (news-paper, life-style, e-mail) and then the hyphen gradually disappears over time. Old enough newspapers still show these words with hyphens in.

I think the hyphen removal follows the typical speech pattern in which the syllables are rushed together just like the syllables of other words, but I'm not sure.