Honestly it is even better on 10man because you can reach your max HPS with even more sustainability. Check the top disc logs for 10heroic, you'll see the trend.
I'm not saying the throughput buff wasn't neccessary for PW:S, I'm saying that a mechanic needs to be in place to make shield spam prohibitive, as it will always be max HPS to do so as long as our MST is what it is and it is sustainable, as has been proven by those with high gear levels.
---------- Post added 2011-02-09 at 06:03 PM ----------
I agree that PW:S is a signature ability, but it shouldn't be the ability that, while spammed, is both sustainable and max HPS.