I can't say I'm an expert all I know really comes from trial and error. I think that is why I'm successful. I fish tourneys so I need to learn from mistakes and learn fast.
I prefer the 3/8 ounce brush jig I can feel it better In all situations windy, grass, rocks, wood, and current.
I have caught plenty of fish in grass with these jigs but if I was fishing deep grass in appx. 12ft I would use a 1/2- 3/4 ounce jig merely so I could easily punch my way through to the fish.
I hope this helps.