The new locking features of V2016 should help those of us who still need to use T2L from time to time. I wanted to mention then when a new entry in a reference list is created in LIVE, T2L will still error if that entry is used, but the recovery is fairly easy. From the error log, identify the reference list item that it was trying to delete, design transfer that from LIVE to TEST and try again. Rinse and repeat and you should get there.
Without locking, whole design pieces can disappear.
You are correct. Although the locking feature will help it will not freeze all design possibilities as you are meant to still be able to use it and add your own values in to a locked module, so the same causion will still need to be used.
Yes, design transfer things created in live over to test before running the design transfer should help you work around this.