If you ask if it can be loaded from the one or the other end, or from both ends at the same time, then yes, it can - just as the Span loop. However, as a crossing-knot loop, it behaves better if it is loaded by the particular end shown in the pictures. See how securely the Tail end is nipped in between the two opposing loaded bights, the first curve of the Standing part and the first curve of the returning eye leg. Also, it is a PET loop only if it is loaded from this particular end, because the one, the crossing-knot bearing link, is TIB, while the other, the overhand knot bearing link, is not.
As mentioned in another thread,
no TIB loop can be 100% symmetric ( yes, this is
always true, and it happens even in the case of the seemingly symmetric Alpine Butterfly loop ...). So, for any such loop, loading from the one end would always be
different - better or worse - than loading from the other.
I find it very interesting, and very convenient, that the
pet loop does not need any transformation / transfiguration in order to be used as a end-of-line loop or as a midline loop. As a "span" midline loop, in particular, it settles in a less asymmetric form than the Span loop, where the bulk of the knot s nub and the eye are not aligned vertically (1)(2).
1.
http://igkt.net/sm/index.php?topic=4354.msg28285#msg28285 2.
http://igkt.net/sm/index.php?topic=4354.msg28286#msg28286
