Howdy hi Kevin,
I have no solid proof other than my own anecdotal evidence and we all know what that's worth. But, I believe, at least in a WSM or Weber grill, "water smoking" simply must aid smoke ring formation versus a drier, no-water-added smoke with all other things being equal.
I always add boiling water to my water vessels--a few bay leaves, too, for a nice aromatic addition! As far as the WSM being a closed system, we know it isn't. But, it is for the most part a considerably/very restricted system.
It would make a very interesting and, somewhat informative, Masters Thesis project. Could easily piggyback a test to see if "water-smoked" meat retains more moisture than "dry environment" smoked meats--all else being equal. Maybe Weber should drop some coin on a University somewhere...
There are a lot of points needing to be kept equal.
a) Comparing same meat cuts from the right & left side of the same critter--all processed, stored and prepared the same.
b) Smoke wood from the same lot--kept and used under conditions that are kept as similar as humanly possible.
C) Automatic temperature control for similar cooking temperatures.
d) Multiple smoke ring measurements from similar locations on each meat tested.
e) Probably a few other things I haven't considered or bothered to mention...
A true test would likely require at least a dozen comparison tests to be done to have enough results for good statistical power.
After all that, I'd bet there would be a statistical difference between the "water smoked" and drier smoked meats--with the "water smoked" meats having a larger smoke ring.
However, the real question would be: Is there an <span class="ev_code_RED">important</span> difference--a difference that is worth the extra effort? That I'm not so sure of...
###