Hey, i just got my HG One and have huge difference in flow speed with just a single step coarser or finer with the same weight of beens.
I have very light channeling in the beginning of my shots, but nothing super major. I tried different distributions including variations of WDT but the differences stay the same. It's around 7seconds or so with a single step. Tried super fresh beans (1-2 days after roasting), then some that were like 7-12 days old and some very old beans. Always same results. I'm using a strega. Also have some grounds in every cup, but very very little (like 10 particles or so). It's all very well cleaned.

I have an HG-One 2014 with the Mazzer uncoated burr set and do not have the same experience. I find the finite adjustment provides small enough increments.

However it wasn't until I ran at least 20lbs and probably 2x that before the taste of the espresso opened up and became enjoyable.

I suggest contacting HG-One...

i have the same burrs - also with just using the tumbler i have major channeling, even though the grounds look nice and fluffy

The steps are really small.
One click adjustments on HG One makes very little difference on flow and cup.
I usually have to adjust 2-3 clicks to see a significant change.

Your distribution maybe problem (don't forget to stir the grounds) or the burrs are not break in / possibly out of alignment.

+1, especially the point about the burrs possibly being out of alignment.

is it normal that going one step finer/coarser change the time to get the same yield by about 6-8 seconds(keeping all other parameters constant)? Does that seem reasonable or way to big of a change?

That is dramatically too big a change! I doubt if even changing by one of the big units (5 small units) would produce that much of a change. One step produces a miniscule change. Something is wrong.

After burrs are broken in one should also get 1 gram ground per turn, perhaps even a bit more for a normal espresso grind. It should be extremely reproducible too. After going from a coarser or finer grind and coming back to the same point on the scale it also is extremely reproducible.

Let's stop dragging hgone through the mud and contact them already if you're ready to blame the grinder. It's apparent your issue is an anomaly. Although to me it sounds like breaking in the burrs coupled with distribution issues or you're overfilling the basket. Make sure you wdt aggressively (in the basket, not the tumbler) and rdt with this grinder.

I notice about a 4 sec change per step on mine. It has likewise been assumed that I must have poor technique. I don't think so and am happy with the results, which are tasty and quite consistent. All shots were pulled to a constant weight (determined per roast). I make finer <4 sec changes by tweaking the dose a few tenths.

I also have to grind very close to the zero point (when burrs first touch) (less than 1/4th turn) - i contacted hg one, i think it might be burrs not alligned but awaiting a bit more info. maybe dhl throwing around the package a bit too much? And i definitely dont want to drag the guys at hg one through the mud, before and during purchase they were very helpful and i doubt they would send me a badly aligned grinder. With bad technique, would i see such big differences that stay Consistent? I also rdt, but tried without it too.