…which makes your other Toughness powers basically worthless, doesn't it? If you have PI with the same catch, then they won't ever (or will almost never) come into play. Anything that doesn't fill the Catch will be blocked by the PI and anything that does will bypass everything.
You're probably true 99% of the time. But people are really digging hard and deep to find ways to abuse the system (an exercise I abhor in gaming), so the language has been adjusted to make it clear what to do in all cases, even if some of those cases are silly.
My take is you should either have:
- A suite of Toughness Powers that aren't physical immunity with a Catch
- Physical Immunity with a Catch (and no Toughness Powers beyond that)
- A suite of Toughness Powers with a Catch, and a separate Physical Immunity with a Stacked Catch
But, given that, I expect hordes of angry flaming poo-flinging rules lawyers to descend upon the possibility of a Physical Immunity plus a suite of Toughness Powers all covered by the same Catch conditions ... so the language is there.