To my way of thinking, today's discussion---among MikeNice, BJ, and Jerms---is central to the core theme of this thread. I call the posted exchanges a "discussion," rather than an argument, because all three posters retained a very civil tone throughout. I appreciate that effort. Although I'm a bit late to the party, I'll add my two cents.
First, about gunking: Back when NETs first appeared in the retail marketplace, which is to say, 2010-2011, when VapeRite and Want2Vape began selling proprietary lines of retail NETs whose tobacco flavorings came from in-house macerated natural tobacco extracts, coil-crusting and wick-gunking may have been mentioned in posts on ECF, especially concerning W2V NETs, but the deleterious effects on coils and wicks were more interesting side effect than an issue in and of themselves. We were so knocked out by having juices that provided authentic tobacco flavors that we (mostly meaning vapers who posted on the original Natural Tobaccos thread) sort of glossed over the collateral damage.
As time passed and other NET vendors began to enter the retail marketplace---as a trickle at first, but with increasing momentum over time---that changed. Especially with the appearance of retail NETs made from in-house steam-distilled extracts by Ahlusion and outsourced steam-distilled extracts by HHV, posters on Part One of this thread began noticing---and reporting---that their coils and wicks were crudded up more by some NETs than others. The neutrality of simple reporting gradually gave way to more and more instances of complaints about what a hassle it was to have to either dry-burn atties or throw out gunked-up cartos. As Part One of the thread gave way to Part Two and the hardware sector advanced into rebuildable atties and wrapping one's own coils/wicks, the complaints about gunky NETs grew louder. And why not? Having gone to the trouble of making a coil/wick by hand and then being forced to mess with it shortly thereafter, either by dry-burning, re-wicking, or starting over with a new coil and wick, who wouldn't complain? That's when crusting/gunking---inevitable with all NETs eventually but very quickly with some---became a hot topic and it's own issue. From that point on, the tendency and speed of a given NET to negatively affect coils/wicks became an integral part of our discussions around how good a juice it was. For instance, the Vapenstein W2V line of NETs is invariably given high marks for depth and intensity of flavors, but now that comes with the inevitable caveat of their being extreme gunkers. The older trinity of flavor, vapor production, and throat hit as judgment criteria have morphed for NETs into the duality of flavor and performance, with vapor production and throat hit being mostly relegated to the rumble seat.
Around the time where complaints about crusting/gunking had become a virtual flood, Diane at MyVapeJuice decided to add a new line of cigar NETs to her original offerings, which, despite our initial enthusiasm at the appearance of a new and major NET vendor, hadn't fared all that well down the road in terms of our judgments about their flavor profiles and performance. Personally, I tend to think that Diane did not make a conscious decision to go for "essence over presence" with her 2nd-generation cigar NETs. Instead, I believe that her decision was probably based entirely on achieving improved performance, i.e., less coil-crusting and wick-gunking, and that lighter flavor was simply a necessary accompaniment. She didn't implement steam-distilled extracts at MVJ, but rather continued making macerated extracts that---and here I'm simply speculating, since I don't know the facts---used more solvent in the macerations (relative to the amount of tobacco) and more sophisticated filtering techniques. More solvent in the macerations would produce lighter colored and flavored extracts, and finer filtering would go hand-in-hand to produce extracts with squeaky-clean performance, relatively speaking. Many of us here were amazed by the pale colors and clean performance of these 2nd-generation MVJ cigar NETs, although some of us weren't thrilled with the reduced depth and lighter impact of the flavors.
MVJ's newest line of pipe blend NETs offer more flavor impact, but with some sacrifice of clean performance.
The bottom-line truth about simple-soak macerated tobacco extraction with PG/VG seems to be that flavor depth, intensity, and impact are inversely proportional to clean performance (meaning non-gunkiness) relative to coils and wicks. Improve one and the other suffers. Other solvents, such as PGA, may alter that relationship ever-so-slightly, but the basic reverse equation remains.
Everyone who makes NETs using macerated extracts---including me---chooses (either intentionally or by virtue of their available equipment and methods) a compromise/balance between these two core variables. Boomer has posted that he goes for flavor all the way---gunkiness be damned. Johni now uses 2.5-micron lab filters, so, in effect, he's chosen cleaner performance. I've gone down to 5-micron filtering to achieve improved performance, but I'm hesitant to go lower than that, in part because doing so will require more expense and perhaps more work, but mostly because I'm happy with the flavor depth and impact I get with my current methods and don't wish to risk any diminishment of flavor. (Johni might assert that 2.5 micron filtering won't do that.)
And so it goes...