That would happen if you would invert the transformer and it will result in an extreme amount of capacitance.
1:1 Bifiliar wound transformers connected in proper phase have zero AC potential difference thus zero P/S capacitance.
Any magnetic collapse resulting into a high primary voltage should result into an equivalent secondary voltage, no change in potential difference and no P/S arc-over will occur.
1:1 Bifiliar wound transformers connected in proper phase have zero AC potential difference thus zero P/S capacitance.
Any magnetic collapse resulting into a high primary voltage should result into an equivalent secondary voltage, no change in potential difference and no P/S arc-over will occur.