Would it be considered "new"?
To paraphrase someone who knows more on the subject than I do... It is difficult to sustain claims of any simple knot being "new" given the tens or hundreds of thousands of years humans (and other animals) have been knotting.1
1Charles Warner in History and Science of Knots, p. 28.
This is what would colloquially be regarded as a "cop-out"
by someone who wished to deny discussions of "new"ness!
Rather, by the supposed Predominance of Evidence theory
this amounts to, one should examine to the better ability
with current communications effectiveness of modernity
how many simple knots are in fact **apparent/presented**,
and I think that then the inference would be that there
really aren't so many, and esp. going back in history with
less-than-happily-knottable materials there are likely not
so many missed!

That said, "new"ness is a troublesome attribute especially
relative to its worth!
It has been my observation that once a knot user reaches
a certain level of knowledge a synthesis begins that regularly
leads to the tying of novel knots. And by "novel" I mean in
the sense that the user has never seen it before.
OTOH, one can visit forums of knot users --canyoneers,
cavers, SAR-ers, rock-/tree-climbers, ...-- and see quite
obvious ignorance of what many should regard as basic
knotting, even ! --and failure to recognize what is put
smack before them, if done. That doesn't fill me with
conviction that the world of knots is well mapped to
some even minimal extent.
I think it would be more useful if the question being asked about so-called
"new knots" in this forum was whether a particular knot already has a name.
If it does not, then a new one can be chosen. This is probably the most useful
function the experienced members here can provide.
"new" could be given an objective definition of
"not included in the <IGKT or ...?> Directory of Knots".
Then there could be a question of whether the maintainers
of such exalted Directory cared to include it, or how soon
they might do so --something one would hope would be
based on the estimated value of the candidate knot. (One
would not answer to every whim to have "Inventor" label
granted by the cataloguing organization!)
As for naming, hmmm, one could argue that names come
about in other ways more helpfully, though also such
origination can lead to difficulties. But as the number
of to-be-named knots grows, there is no happy solution,
so far as I'm aware. I've tried to stamp out what I've
thought to be actively harmful names --the "double
fisherman's" or even "fisherman's" applied to the
strangle noose (scaffold knot), and so on, but I'm yet
to figure out a good way forwards, in general. (For the
sake of study, I suggest some **knot-ID** system,
which isn't so happily conversant as *names*.)
- - - - -
I think this would be a misleading name.
+1, yes. The sequencing of "double, triple, ..." is already
implied by extant naming.
--dl*
====