But, most have a handle for each "phase" and employ internal trip and the handles handles are always tied together.
The internal trip ensures all the "phases" will open together but the tie handle may allow a "phase" remain closed.
I don't understand what you mean "Breakers with handle ties are not 2 pole circuit breakers".[/QUOTE]
I meant two single pole circuit breakers, adjacent to one another, joined by handle ties may be used for MWBC's.