There is no flavor enhancement from the mustard, except salt.
Make your own mustard and you can control the salinity, flavor, and heat. I found a recipe and make my own. I don't remember where I got it, but, I think it is Alton Brown's, with maybe a few changes. There is a trick to it, but with practice, you can find a flavor that suits your needs. Your friends and family will be impressed. Here's the recipe, but READ THE NOTE
Once mustard is mixed with water an immediate chemical reaction begins. The longer it remains in water, the hotter it gets. Acid (vinegar) will stop this process. Once the desired heat is reached, adding the acid will allow the heat to remain at the desired level. Don't wait too long before adding the acid, or you may find that you singe the hairs in your nostrils.
1/4 cup dry mustard powder
2 tsp light brown sugar (I use dark brown sugar)
1 tsp salt
1/2 tsp tumeric
1/4 tsp paprika
1/4 tsp garlic powder
1/2 cup cider vinegar
1/4 cup water
1/4 cup mustard seeds (I use yellow seeds)
Grind the mustard seeds in a spice grinder to desired texture. (I like grainy) Mix with dry ingredients. You can either mix the water and vinegar then pour into the dry mix and stir, or pour water only into the dry mix and stir. If you pour the water only, add the vinegar within the next 20 to 30 seconds to achieve hot mustard. Mix well. Put in the microwave on high for 1 minute. Remove from the microwave and puree with a stick blender and allow to cool. Cover and store in the fridge for up to 1 month.