Thanks for the insight. The scenario you pointed out is exactly what I'm worried about--getting to the gate technically on time, but between waiting for other pax to deplane (I'm in the first row of Main Cabin) and possibly getting a gate-checked bag (I assume there won't be room for my carry-on, and I'd rather not check my bag in case I get stranded in PHL) not making it to the next flight before the doors close.
If anybody else has thoughts on whether this would be covered by Chase, please let me know!