"mirrored girth hitch" is wrong/misleading : it is the bowline aspect that is *mirrored*, which is equal to a girth hitch--which is not (itself) mirrored!
Correct, but tell it to the author of the reference... And propose a better name.
one might prefer sooner vs. "last" defence for strength.
When the defence is stratified and arranged in many lines, it pays to have the first lines weaker than the last ones. Otherwise, if the first/stronger line is somehow defeated, all the others will be defeated, too, in their turn, one by one - because if the first/stronger line would be proved to be weaker than the enemy forces, the next/weaker lines would not be able to stop them either. On the contrary, weaker first lines consume part of the enemy forces, and if there is a chance of a successful defence, there will be some resistance left and intact at the very end, and the last/stronger line will hold. Every general, from time immemorial, knows this strategy, I believe it is about time for the knot tyers to learn it, too !
Because I have seen the same thing in knots. If the tail is blocked in more than one points, say, two, it is much better if the resistance it confronts at the first point is weaker than the resistance it confronts at the second point. Otherwise, if the tension is not enough to overcome the first obstacle, the tail runs the danger to remain slack, at the segment between the first and the second points - or, if the tension is greater, and succeeds in forcing the tail to slip through the first point, it will probably succeed to force it slip through the second point, too. A gradual, progressive absorption of the tensile forces is always preferable - moreover, it will keep the tail tensioned throughout its entire length, so the whole nub of the knot will be kept more compact most of the time. I am not sure that I have been able to describe this fact verbally with my poor wording, but I have tried to offer some points - I believe you have to connect the dots by yourself.
a version of this in which the tail skips collaring the eye leg and instead just "EBDB"-like loops around the 2nd nipping turn to tuck ONLY into the initial nipping turn, where the 3 diameters might matter, for strength and improved curvature.
A much more complicated pattern ! ( Much harder to remember how to tie...) Look at this loop with a fresh eye : Just a double nipping loop ( be it of the girth hitch, or of the double nipping loop of the Water bowline), and a second collar, symmetrically positioned ( mirror-ed), at the other end of this double nipping structure. One
can not forget how to tie this bowline - and any possible mistake would be apparent at the spot.
I have not reached this loop following this line of reasoning. I have just tried to find out which bowlines have a nipping structure that do not need the collar structure to stabilize themselves -or they need it only in a limited degree. A bowline with a self-stabilizing nipping structure, will not capsize as easily as the others, even if the collar is left slack. ( That does not mean that the collar
should deliberately be left slack, as I will argue at my next comment ). A tail that does not bear the role of stabilizing the nipping structure, would probably be better suited to act more successfully in its prime role : to be attached to the standing part, by being part of an effective collar ! The Water bowline and the girt hitch bowline, as well as the double, crossed nipping loops bowline presented at (1), are examples of bowlines with almost self-stabilizing nipping structures. So, the two nipping loops are not needed/utilized to offer a greater sum of friction forces, or a more effective nipping power - although it is possible that they do, indeed, we are not sure that
two nipping loops offer a more effective grip on the tail than
one ! ( We have to
measure it, some day in the next century...)
I would leave the collar around the SPart less tight.
On the contrary, I believe that a tightly dressed knot, being more compact at the first place, right from the beginning - that is, even before its loading - is working better as one piece, one integrated whole. The tensile forces running within its elements would have a better chance be distributed into the whole knot s nub, to be absorbed by a greater portion of the rope segment, so there will be less danger for an isolated small area to bear the full power of the loading, and to become the weak link - a guess !
1)
http://igkt.net/sm/index.php?topic=3951.0