As I mentioned above I had never thought of using a a/p array to enforce fault tolerance but it's true it does help avoid over subscription by strictly enforcing it. Performance on the A/P array would be the same after a controller failure while a over subscribed A/A will have a major performance issue. It really makes sense why so many Solid state arrays are A/P (beyond some architectural issues) It is very easy to over subscribe SSD.
Thanks again for opening my eye's Chris.
Let us both know if you have any additional multipathing questions.
Thanks,
J