[infinite93]

someone did the math a while back (I think it was on Yoda's old AL page). If I remember it right, the basic Idea was as follows:

If you compare a person that does not promote, vs someone who promotes to say, level 4 over a certain period of time, the person who promotes is behind for a while but once they reach their chosen level, the extra career points you get allow you to quickly pass up the person who doesn't promote.

It is just a matter of long term planning. Spending the points right away is great for short term gains, but if you are planning on being around for more than a couple months, getting at least a couple of promotions will make you stronger in the end.