I completely agree, but from the perspective of a software developer I can completely see why they made their decision to implement it this way.
Ease of implementation, significantly less chances of game breaking bugs, significantly less balancing (every class gets a nice little buff, blm and brd don't suddenly have more chances to proc for spike damage, and smn/sch gets a larger buff as it affects their core damage).
With the added bonus of being able to place more focus on other aspects of the game (e.g. polishing/balancing the new jobs).