I am also a Pilates certified instructor and agree with Annette. With the proper technique the neck muscles are not engaged and yes a lot of talking in Pilates.
I also agree withn Marie because I also had no core after my pregnancy. I was surprise to experience having no core because I could not get up at all, even though the baby and belly were gone. I had to really work with the roll-ups to re-develop my core. This also allow me to experience what other people go through when their core is weak and they need to develop the strenght. The post-pregnancy allow me to relate and connect to others in similar situation and walk them through with the proper technique and description.