These all trigger at the beginning of your upkeep, including things like the Honden of Seeing Winds, which gives us lots of card draw, Honden of Night's Reach , which is incredibly efficient hand destruction, and Honden of Infinite Rage , which is part of our win condition
So yes, when you replace an instance of card draw with dredging, youre milling cards, which counts for the purposes of Zellix, Sanity Flayer, for example
They are affected by things like high-profile tournaments, set releases, PTQ schedules, and what sets are seeing the most Limited play
Those are niche interactions, but it just demonstrates that both these equipment have points in their favor
So if you happen to luck into two copies of Krenko, Mob Boss, you can use both of them as your partner Commanders, swapping back and forth between them to delay commander tax increases