Is it wrong that I like this cranked almost all the way up?
I think the feeling of sag is what initially attracted me to my first tube amp. I liken it to a kind of resonance between the player and his/her mind. It reminds me of some ridiculous but liked leads I came up with using a delay, with the dry signal turned off. The slight, or not so slight lag time induces a creativity that I can't explain, but its like some sort of "auditioning process" that stimulates me to add nuances to the notes I'm holding, or to hear things in a way.
But unlike with the dry-off delay stuff, which works better at more than 100 ms, for me the sag effect breathes, and I still get reasonably little of an actual latency effect, but it seems that there is sort of a textured latency unevenly applied to various parts of the tone. I have no idea what this would look like graphed out.
A sustain pedal on a piano also has this effect of heightening my creativity. But with the guitar and sag its different - it nurtures creativity also, but its more of a melting of the "idea you thought you had" into something different, whereas with sustain on a piano (and long, eg cavernous, reverb on a guitar?) its sort of a wide open palette that sticks musical paint to one, and so doesn't so nicely keep moving out of your way after it inspires you.
During a lot of fast shred lines there may be no chance or need for this kind of creativity, that involves slight changes in dynamics, pressure, vibrato and such. With them I suppose its better that the intensity of the line is conceived of fully, moment by moment, and that's okay.
Its the "between the moments", or overlapping effect of sag that I like.
Frank Marino comes up with insanely good note bends and ideas because he gives himself a lot more room to breath within "the time", and I suppose its similar for me with sag.
On a lot of medium or lower gain sounds I usually like sag very high, and for me there is no longer any shame, although when I had my Ultra I did use to wonder what was wrong with me.