[GrumpyGramma]

a test designer is requiring that we be able to create a needle that is 180" long for an adult dress,

I'd either do as I please or not do the test knit. I can't imagine using a needle of that length and if it's a non-negotiable requirement then the designer needs a wake up call. My response to your question is that if it works for you it's right and what difference does my preference make?

I can make 60" circs and sometimes do. They came in handy for two at a time slippers with lots of stitches worked along the length. They could be used for blocking in lieu of blocking wires and I'm considering putting them to that use on a shawl. I use them as stitch holders for trying on top down sweaters. They have their uses but not often for knitting

 

[GrumpyGramma]

Your preference does not make a difference, I'm just curious. I have joined the test but will knit as I please, it's not like the length of the cable makes a difference to how the piece comes out.

In that case, I much prefer magic loop for small circumference knitting. I can and have used two circs but do not like it. Overall I don't like a lot of extra cable, ever, either knitting flat or in the round. Actually the length of cable can affect how my knitting comes out. If there is too much length I can end up with uneven tension when moving stitches along. That might be an idiosyncrasy peculiar to me alone and it took me a long time to figure out the problem. Typically I use the shortest needle that works. I would do as others have said and use multiple circs like long floppy dpn, knitting with another.

 

[GrumpyGramma]

I have no idea either but lately I've encountered more tests where the designer will specify so many things. It used to be that they would give suggestions but say, "or your preferred method" for cast on and bind off, except when a special one like I-cord or tubular was part of the design .I've even seen ones that want some to use circular needles and some to use dpns, there was one where the designer specified Magic Loop only.
If it doesn't make a difference to the final piece or checking the pattern for correctness why should they care?
On the other hand, I also test for some of the nicest designers who give a lot of leeway in the testing. That makes so much more sense since the more options you can display for a potential buyer the more patterns you will sell, IMHO.

The first two words that pop into my mind are control freak. In an attempt to be fair I think that so many knitters expecting everything to be spelled exactly and precisely could be part of the reason for specifying how it is to be done. That's why we see questions like, the pattern says to use dpn, can I do magic loop or it says magic loop, can I use dpn.

 

[GrumpyGramma]

Yes. A couple of years ago I did a test for an adult size, floor length, crochet caftan done in lace weight yarn. I loved it but GD appropriated it.

Kids. The things we let them get away with even when they're grown. 🤣

 

[GrumpyGramma]

If they tell how to divide up the stitches on the needle and/or number the needles etc then it could be important to use the method said. You need to check that the pattern works for the way it is written, not the way you want to knit it. For example if the pattern has needles numbered 1-4 then you need 4 needles (or divided into four with markers) so you can be sure that has the correct number of stitches on each needle.

Of course if you are simply following a pattern rather than doing test knit you are free to use whichever method you want.

When I do a pattern for dpn on a circ I use markers to indicate the end of the stitches on a needle. I'd still do the pattern the way I prefer. It would be my silent rebellion against trying to control my knitting.

 

[GrumpyGramma]

And that would work and still enable you to do the pattern as it is written.
But it seems to me that if you are doing a test knit you need to be prepared to have your knitting controlled. You can't just change something in the pattern if you want to and so you are being controlled. You can't adjust to in the round or flat because you prefer it that way so you are being controlled.
So unless like using markers to mark needles rather than using DPNs (which is what I would do as well as it is effectively using DPNs as you can still have needles numbered and I don't like DPNs either) you need to follow the pattern exactly as written. And cable length would fit this category, using a smaller length as long as can still follow the pattern exactly it won't matter. And indeed it would be one of the points you would make to the designer that the cable length seems to be far too long.

Of course if you are following a pattern rather than doing a test knit then how closely you stick to the pattern is totally up to you.

I'm doing the same test knit as J-J. I decided to not only because I love the pattern but the general idea seems to be to follow the pattern and use the tools and methods you want. It starts with a provisional cast of choice and no requirement of a specific one. I agreed to follow the pattern when I took on the test knitting, totally my decision and choice, so ithere are no designer control freaking issues to contend with. I knew I'd be following the pattern. I soon realized I can do the cables thus far without a cable needle so again, my choice. After a huge amount of frustration because sometimes I just miss something it's been enjoyable so far. I'm not sure I can meet the deadline but I'll do my utmost to finish on time.