Yes. I favour that approach myself. It may seem disorganised to folks who always stick to 'the plan', but it's actually more truthful. In order to be truthful to your characters, you sometimes need to change the plot you dreamed up before you knew them as well as you do now. Otherwise plot and character aren't going to fit. It makes the difference between reaching the end of the story (as a reader as well as a writer) feeling satisfied, and reaching the ending feeling that something isn't quite right. Buuut that character wouldn't DO that, would he? Instead, he'd....
