The reason "that's the way it's always been" doesn't fly is that the way it's always been is that the GOPe candidate always wrapped it up after Super Tuesday, or shortly after, so that the actual delegate selection process was pro forma, it didn't really matter.
Now that we have a true electoral contest, we are seeing the flaws in the process, meaning we are seeing all the hidden back-doors that were always there but never used, that are being used now to undermine the will of the voters because the GOPe finally lost at the ballot box.
That's what has the people so angry. It's not that the rules were always there, it's that the rules are designed keep the establishment in power.
-PJ
I have to wonder how many of these people bitching about rules have ever been to a meeting?
The rules were designed to give an extra weighting of delegates to the frontrunner after the early primaries are over.
This was supposed to be some conventional politician. Trump is benefiting from the system the establishment put into place.