Ummmmmm to me; a Cow is like a sling choked with 1 leg cut open; it is best if that leg is then stoppered or secured.
They both start with a Back Hand Hitch (which if placed on a krab is more familiarly called a Muenter); but with different finishes. Cow comes back thru where first leg did, to form like a choker on 1 leg so can make by grabbing eye and tail and choking around and releasing tail/ bitter = Cow Hitch. Timber makes a loose braid around self to finish (after Back Hand Hitch), so is more dependent on convex mount at nip points of braid. Each is stronger if taking a Round Turn rather than a single Turn around standing; like a dbl.Noose does (see both ABoK 1669 pix, and note also another feature, how the first tuck doesn't come under immediately, but goes over, then under).
As a Timber can also be described as a form of Half Hitch (not the kind of half as precedent of running Bowline etc., but the kind as hitch formed around self); a little study of these pics from ABoK show that it is best to not tuck as soon as possible on braid of Timber, but rather go over, then tuck(see fig.8 Hitch #1666, fig.8 Timber 166
. This gives extra frictions and places that tuck farther from Standing (see Anchor simbol by Half Hitch w/ better Nip ABoK 1663 vs. skull symbol on regular Half Hitch ABoK 1662, or even how slipped 1664 is better than 1662) . At Standing position, we have the most force pulling away from spar/ mount, so least trapping pressure. In fact increasing 'twirls' / 'braids' give extra securing frictions(that reduce the pull against subsequent nip positions) and nips/ traps-but the most important feature would be to finish or at least pass thru the point opposite of Standing, that pulls tightest into spar, to secure most, like in
If pulling straight away , perpendicular from mount, things are kinda neutral, but if pulling along the spar / mount, prefer the Turn / Round Turn around Standing to be against the direction of pull. If less line, will go with Timber, if there are flat spots or indentations around mount, go more with Cow. Have, with more line, gone kinda hybrid from Cow, to the Timber braids, finishing with tuck/ slip opposite Standing.
Notice how all these hitches are for right angle/ perpendicular pull to host spar / mount; thus pulling along length of host spar / mount is a bit compromised (notice reference slightly to this in #1733), use extra care, don't pull into reducing taper, try to dawg on imperfections / swells and /or cut own bedding kerfs or humboldts for such to lock into is most positive. MR. Ashley in his ABoK bible even separates pulls perpendicular to the spar and pulls pairallell / along spar into 2 different chapters- that are right next to each other, because of these mechanics, defining them as separate and distinct.
Many knot secrets in these simple pages below. Though off topic; notice the sweet simplicity of mr.1709(and it's comments) for utility apps.
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