The vinegar is for the first time you use the gi, preferably before you wear because the acid in your sweat will throw things off.  It is not necessary to do it for every wash after this. 
Also, you want cheap white vinegar, not your expensive balsamic! 
 
A little baking soda in the wash changes the PH and helps neutralize odor. Don't overfill the washer (one or two gis at a time, tops) and I find a second rinse really seems to help take care of the funk.  After you get the gi to the size you want never use heat or your gi WILL continue to shrink (@#$! Canada ruined one of my favorite gis that way [Canada my school parnter, not the country]) 
I don't necessarily wash my gi after every use (depends on how much I sweat), but always spray down with antimicrobial Febreeze every time I use it. 
Me being me, I also have a lot of gis I can cycle through (hell, I'm on the mat six days a week so I need a lot of gis).  But being able to cycle through really saves on the wear and tear as oppossed to the very early days when I only had one or two gis.