If smoking sausages there are two primary techniques. Hot smoking is just like cooking a piece of chicken or other meat in that you are really soaking to temp and consuming the meat immediately. Making a “smoked sausage” or cured sausage is a different process using curing salt in the blending process and smoking at a much lower temperature. Cured sausage has a saltier flavor and different texture. Think Kielbasa, summer sausage, etc.
Pre-poaching fresh sausages is a great technique to ensure that fat from sausages doesn’t cause flare ups when grilling. Because most smokers cook using indirect heat, it is an effective way to cook sausages without burning.