? water pan smoking sauage

The pan diffuses the smoke and heat, roiling it around in the smoker and evening things out.  Put water in it, and you get 2 benefits: temp stability and moisture to keep things from drying out.  Put extra goodies in the water, and some say you will add flavor to your final product.

Were your 2 smokes comparable in time, smoke generation, cook temps, etc?  There are a lot of reasons why those 2 batches came out differently.

I agree with temp stability and helpfull moisture, always use pan with water for mine.