Yes, Jack pre should break with the CR/LF it was supplied with but outside the pre won't.

If writing a routine to handle the post's contents, the simplest way to handle this is probably to use a global search/replace function and change all CR/LF pairs to br. My leave pre alone version would have to scan through the post, to see whether in a pre or not and act or (otherwise) on the CR/LFs encountered accordingly. Personally and talking about elsewhere. as I don't think this substitution does cause a problem, I use the simple method.

Re. Not believing it is a problem, if you step back a few posts and look at the source for the post where you seem happy with Gleanntain Ghlas Ghaoth Dobhair, you will find there are line breaks within the pre. You have just eliminated the leading spaces.