I'm sorry, I'm not in your ddc and haven't read the whole thread, but I saw your title and wanted to respond . . . Dd was a VERY gassy baby. She has severe food allergies and this is how it first manfiested. It is my very strong belief that most infant gas and reflux is due to food allergies. I would keep with the eliminations--how strict are you with dairy? Be VERY strict, like no dairy (whey, casein, lactose, cheese, yogurt, milk, ice cream, cream cheese, etc) from any animal at all ever. Gluten and soy are also very common allergens. I have heard that alliums (onions, garlic) can be common causes of gas in breastfed infants as well.
Infant reflux is a serious condition and deserves to be treated. However, you should know that acid blocking medications inhibit the absorbption of minerals (calcium, iron), because minerals require stomach acid to be absorbed. These medicines should be taken very seriously and should only be used for as short a time as possible (ie while you run some eliminations and see what's bothering the baby). My daughter developed severe pica after 15 mo on reflux meds because she wasn't getting enough minerals into her system, despite an excellent diet.