...the straight entry of the eye leg produces what seems to me to be a significant change in behavior. Rather than laying loose like a braid, it compacts the knot tightly against the nipping loop and enforces the tightness of three 180-degree-plus turns.
If you prefer tight, compact knot nubs, you are right. In that respect, this bowline is a new knot, indeed ( at least to me - I have not read Harry Asher s book ) - because you have chosen to pass the continuation of the returning eye leg = first leg of the collar
under the second leg, and this seemingly insignificant detail can make a great difference, in so simple a knot (*). However, the advantage of the genuine braided bowline ( but, to some degree, of the pseudo-braided bowlines, too ), was not meant to have any relation with compactness : as its author said, the braided structure around the Standing end above the collar is able to absorb sudden pulls, because it acts like a spring absorber.
Regarding security against slippage, we can not say if a compact nub offers more or less ! The braided structure, as the Malvolio stockings "
cross gartered" structure of the ABoK#1755 / #1756 and of the rat tail stopper, are not compact, but they are more secure than all the other compact hitches around ropes able to withstand lengthwise pull.
(*)
In the [ knot shown ]... we can keep the standing end as it is, and interchange the two legs of the bight component / collar structure, so the direct continuation of the eye leg of the Tail side becomes the Tail, and vice versa. I have no clue which of the two variations of each knot is more secure...