My understanding is that the Frequency is a rebranded Supra. My fiancé has one and it’s a decent line. I had a Mastery Trout DT some time ago and I got rid of it as it had some memory issues thus it was not as limp. But my brother has one and did not have that issue. The 406 are nice lines and many people love them. They have a great color and taper. I would say they are in the realm of limpness as the Supra, but I would really have to handle them side by side, and maybe I can do that in the next few days. But I think they might be slightly limper. But would have to handle them again to be certain. They float just fine, especially if you wipe off your line regularly. My only complain with them is they are not very good shooting lines. I am not guy who generally shoots a lot of line, but when I pick up the fly after it floats over a rising fish I like to pick it up and lay it back down over the fish in one cast. They don’t do this very well, and it is more noticeable on weedy or “dirty” rivers like the Henry’s Fork which I fish quite a bit.
I supect it may be due to its softer coating. But that may be no concern to you?

Another consideration would be the Sylk. It’s also one the limper lines available, and available in a DT. It’s a decent line too. My only nitpicking with it, it does not shoot as well on hot days. Many folks may never notice this, but if were using it in a boat casting to risers, you might. I also suspect it’s on the lighter side, but I have never weighed it.

If limpness is your primary desire, maybe you should consider a silk or artificial silk line. No current line can really compare. The only other consideration would be to obtain a old stock Masterline. They are the closest plastic line to silk there is. But they are not the best floaters, but one can dress the tip or line with otter butter if desired.

As a side note, my current favorite plastic (other than the Masterlines) lines are the Rio Techinal Trout and the Rio Lightline DT. I probably prefer a Lightline a wee bit over the TT. They may be worth looking at as well…

Otter butter?? And while we're on the subject of potions to apply to lines, do I remember a spray-on silicone product?

That comment about the Frequency lines being close to the Supras is very interesting to me. And, yeah, I like to shoot line out past a missed take, too, so delicacy is my first priority (limpness has a good deal to do with that), floatability is important, and then shootability. But I have my limits. As in, I AM looking for a DT rather than a WF.

Fish on!
Peter

I haven't tried a new one in quite a few years but the Cortland Sylk is probably the most supple line I've cast. It's available in DT.