Glad you have more information to work with now, even if the answer is not really cutting the mustard.....

I was induced with gels with my first, baby was pretty high at the time. Labour started about 5 hours later and baby was born after 2.5 of labour. So yes it can certainly do the job and you are right, as your body has done it twice before it may not need much help to get underway. I was supposed to have 2 doses of gels hoping that would get my cervix favourable enough the break my waters. So even if the gels don't work as you want, they may still help you get to the next step to meeting your baby.

Goodluck.....x