It's always good to be able to see the bay and what kind of hog you're dealing with before you release... but it doesn't always work out that way. If we can hear some fussin' going on we'll send em in from 100+, but if we can get in close to see what's going on and be right behind, that's ideal. This may not be the best way, but it's how we do it.
X2! Always good to survey the situation before you let the catch dog/dogs go. Had a friend in east Texas who cut his pit loose without seeing the hog and he then had to handle a three hundred pounder by himself. The end result was a cut dog and a cut up hog dogger.