Glad to hear more use the slipknot method; it is my favorite. A real easy finish on the ground is if standing part is anchored, then back up away from it to pull lacing into position from slipknot phase. Or, in tree, allow the weight of the standing part to pull knot into finish from slipknot phase.
2+meg vid of tying DBY using this slipknot technique. . Though backwierdz like my other stuff; this is an easy way to tie the DBY;
250k animated .Gif-tying DBY behind back . Notice in both; we keep it loose, so it can slide into place easily.
i first read about the slipknot method; when it was called the climber's method(so i had to learn it). If a climber was stuck on a shear face; from an overhead lip or by helicopter; they would lower a line down; and climber could hold on to position with 1 hand and form slipknot with other, work bitters around under armpits, then into slipknot, without letting go of handhold. Once correctly done, climber could even fall, and if they held the bitters pinched to standing part, the falling action would set the knot! Then i picked up the double bowline, then later saw a yosemite finish, and combined all 3. It has been my faithfull friend.
i believe becuase of the larger/softer curve it is stronger as you say, and also more secure. But, it does pull from a higher, 2nd tier, so has more leverage to deform, if not dressed properly i think.
Thee extra strength is in the round turn/double/mountaineering version shown; but not in an extra turn laid into a clove hitch as choker for a more secure Water Bowline, as the larget /softer arc effect is lost, even though 2 turns; they are 1 at a time. Another attribute besides the 'clean eye'; is that i think a DBY is more symetrical/easier on eye/ easier to quick check; such as usually attributed to the fig. 8 family by mountain/rescue.
Another advantage to making the bowlines with the slipknot method, is that you can stop and lay it down, or hang it from thumb etc. before finishing. Then, quickly fininsh/trap when device is brought to you, or other line stretched to you etc.
And, a real obscure notion, kinda from KnudeKnoggin's method, then screwed around by me a
DBY method; maid in the bight!. Though, ya need to primarily load (first and more) the standing part.