Heavy current will flow inside the stabilizing tertiary winding during an LG fault on secondray side. To give an idea of current, in a typical 10 MVA 132/11 unit, Vz= 10 %, the tertiary winding will see 3 times rated current without LV feed and may increase above 7 times with LV feed.
In small transformers we eliminated stabilizing winding in India due to tertiary winding failures from the dynamic forces consequent to over currents during LG faults on secondary lines.