Yes, it's supposed to work by encouraging effacement and help to reduce or eliminate tearing when delivering.
I wouldn't use if already dilated not really any point if it just softens up the cervix which is already doing good job on its own :)
I was told it doesn't help induce it just softens your cervix and prevents tearing. I've been using it for 2 weeks and mines nice and soft but still 0 cm dilated at 39+ 3