Beginning […] The End

I know, usually, where I’d like to start.  I have my point A.

I know, usually, where I’d like to end.  I have my point B.

For me, it’s only natural to write what I know, and wait for inspiration to show itself so I can write a part here or there.  The Worldtree Trilogy is a mess of sporadic passages and half-finished chapters, written whenever the mood strikes me.  (My poor boyfriend is my acting editor, and he no longer has any idea what the timeline of events is like because of this.)  I’ve been trying very hard to write in a linear fashion; The Bizarre is the first project written mostly in order.  But I recently had a huge bout of inspiration for the end, and, so as not to waste it and forget everything, I fell to temptation.  I wrote the end.

So, I ask you, how do you write?  Is it a bad habit to write the beginning and the end and fill things in as you think of them?  Is it bad instead to try to force things in a linear manner only to be disappointed by the course of things later?

Am I weird, or is this normal?