I'll be interested to hear the results Jeff... so please keep us posted. I too think that a lot of people get caught up in the hype that is "bow speed" when in reality it doesn't take as much speed as one thinks to take down a deer. Now other animals with thicker and tougher hides... maybe.
I too have been debating messing with my arrow as well as poundage to see if I can achieve more accurate flight versus speed. My Guardian is LIGHT YEARS ahead of my old PSE Baby G-Force in regards to speed and quietness. However, even though my Baby-G is a good bit slower than my Guardian... I never had any problems with pass throughs or speed while in the woods with that bow. It was and still is an amazing bow and I keep it as my backup. So in my opinion... my Guardian's speed doesn't really matter all that much to me seeing as I was able to do just as well in the past with a slower bow. Also, when I was shooting my PSE... I had absolutely NO knowledge of arrow spine... that knowledge didn't come until 2 years ago when I really started to research (I'm 27 and been bowhunting regularly for 13 years now).
All of my shots in the past were with Muzzy heads, so obviously I can't comment on the lack of pass throughs with the Rage expandables. That doesn't mean I don't have one in my quiver to test.
Like I said... keep us posted... I'm curious to see the results.