I've done it often. Said goodbye to a character who wasn't carrying his weight. Given the ax to someone who was the same as somebody else.
I could read every word Laurie Halse Anderson writes about writing (not to mention quite a few of her fiction words).
Click for her thoughts on the subject:
Here's a bit of what she advises:
1. List all the characters.
2. Define – using only a few words – that character’s relationship to the main character. Examples: comic foil, trusted friend, villain, complication, love interest.
3. If (like me) you have two or more characters that serve the same purpose, get out a magnifying glass and sharpen your scythe. Is it possible to have one of the characters take over scenes from the others?
In my past book lives, I've said goodbye to a boy named Zach and an aunt named June (or maybe it was May. My critique group laughingly called her Aunt May June because we never could remember. That right there tells you something about how interestingly she was written).
Possibly a lot of my characters have left the building. And have long been forgotten.
Have you had the nerve to chop a character right out of your story? Scary, no?
But totally worth it in the end!