We are past the point of diminishing returns on power and revs.  I say this partly based on Belmos struggles, but partly based on the physics and geometry of of the game in general.  Belmontes success has been partly due to his power, but also to a great degree on his versatility.   The problem I am seeing is that the super powerful rev rates magnify the impact of lane transitions to the point that super power players simply cant keep up
  To me it is no surprise that a player like Rash who has totally revamped his release to minimize axis rotation ( the real culprit in extreme lane transitions ) is starting to dominate.

I think too many times we look at isolated incidents and make assumptions based on this small sample size.  Watching a couple of shots on the 52 feet of oil on the match between Belmonte and Tackett showed both bowlers keeping the ball inside 15 all the way down the lane.  Both had some carry issues as is expected on a fresh shot of that length.

But what we don't see is how bowlers get to a typical finals show and how the styles perform as the lanes transition from fresh oil to broken down after 8+ games during qualifying.  It is in these instances the high-rev, high-speed releases are of benefit the most, or at least that is how I see it.

The most successful bowlers will take their release and have the ability to adjust ancillary aspects to be successful on whatever condition they are encountering at that moment.  Going from low rotation up to high rotation along with loft and other changes (all the while doing so consistently at the correct time) will make the bowlers successful.  And if everyone can do that then I feel the higher rev and speed guys will be more successful because of the ability to overpower the broken down lanes at the end of a block.

What pinbuster said is spot on.  Very small variations in release at super high rev rates and large axis rotation are magnified, just as small lane transitions are magnified.  As for Rash dominating I probably over stated, but has clearly made himself more competitive over a broad range of conditions by cutting his axis rotation way dowm