This problem is based on time and intensity. I have not evaluated the effects of opposing, out of sync, flux. Circuit breaker time /trip coordination is the only way the breaker will remain closed, on a hard start.
In the past, I have froze brakers with freon gas, to enable a transformer to be started.
I was incorrect when I stated the load on the secondary was not a factor. The current flow in the secondary will delay the primary flux build up, extending the time. There could be some effect on the secondary load equipment, concerning out of sync fluxes. I don't know what this effect would be, I'm only mentally examining this possibility.
Transformers, at initial start up are essentially a dead short. There must be overcurrent devices capable of providing service continuity.
