[Jellby]

Originally Posted by mores

1) replace double-line-breaks with XXXXXXXXXXXX
2) replace single line breaks with a space
3) replace XXXXXXXXXXXX with double line breaks

Wouldn't the same be attained with:

1) replace character-linebreak-character with character-space-character?

(In vim: %s/\(.\)\n\(.\)/\1 \2/ )