Okay, by default, you get exp for ECL. Yes, he records how much everyone gets and gives it out based on level.
So being lower level grants more XP (to an extent).
So if you are level 3 (from crafting lots of awesome gear) you get 20-30% more XP than a level 4 if the party is basically all level 4.
However, some DMs don't use the default rules for individual XP and instead make up a number of Xp for everyone equally. Not RAW, but easier than doing the math I guess.