The rule changes won’t impact the current existing delegates, but they are sure to give candidates the power to disenfranchise elected delegates in the future - and that still isn't right, imho.
Many delegates to this convention will look at it as what it is - allowing a marginal candidate (like Romney) to disallow votes from states that don't vote strongly for the candidate.
The future to the Establishment is Jeb Bush (Romney said that he wouldn’t had jump in the race if Jeb was running)
It sounds to me like some of the rules changes are designed to make it so that the RNC and Romney can unilaterally change the rules in the future without needing the approval of the National Convention. How does that kind of raw power not benefit Romney and the RNC if he wins the White House? Even if the new proposed rules don't benefit Romney in this current election cycle, the rule changes could still benefit Romney in 2016 if he runs again.
Besides, the rule changes are inherently autocratic, and lead to a gross amount of power to the Republican National Committee. Better kill the rules quickly while you still have national delegates that have some sort of voice in the process.