Realistically it is a shortcut, and whilst the "heat glue" has imporved over the years , it can delaminate over time or washing
This can happen, yes, but doesn't matter a hoot. Consider that sew-in interfacing is just a layer of cloth. The only difference between it and a fusible is the heat sensitive resin. As long as the fusible was applied correctly, and finished properly (no exposed edges), I have experienced no issues on having a fusible delaminate.

What I have had issues with, is the non-woven 'fabric' that some interfacings are made from. With heavy wear and repeated washings, it can sometimes fall apart or 'whisker' itself to nothingness. I always try to go with woven fusibles over non-woven.