Witch Hex Questions

[Coleridge12]

Many witch hexes are worded in ways I find confusing, or have ambiguities I'd like help clearing up.

Combat Hypnosis:

Combat Hypnosis states that it works as hypnotism. Does this include the 2d4 HD limit? If so, is this an instance of planned obsolescence for the hex? Having two points of failure, such as targeted a 3HD creature and failing by virtue of a poor 2d4 roll or by that creature succeeding on a saving throw, as well as obsolescence once you start meeting 9 HD creatures seems strange amongst other hexes that usually remain valuable and can't be easily swapped out.

Scar Hex:

Scar hex states that a witch can use her hexes on a scarred target from up to 1 mile away. How does this interact with hexes such as Seduction, which states that the target must be able to see the witch, or Waxen Image[/ur] which states the witch must see the target?

Withering Hex:

[Url=https://www.d20pfsrd.com/classes/base-classes/witch/hexes/hexes/major-hexes/withering-su/]Withering Hex ages the target and buffs the witch, then says that "these effects" last for some number of hours. By "these effects," is it referring to the aging and the buffs, or just the buffs? Is it intended that the target can never be affected by the hex again, unlike the usual 1/day limit other hexes have?

On a minor note, I notice that many witch archetypes replace the 2nd, 6th, and 8th-level hexes. What's the design behind replacing hexes at these specific levels?

[ErichAD]

I can give you my reading on them, but I admit they're ambiguous and there will be people who read them differently.

Combat hypnosis replaces the targeting info with the "1 target at a time" info. That would mean losing the 2d4HD worth of targets and the aoe.

Scar hex only alters the range requirement. You'd still need to fulfill line of sight or line of effect requirements.

Withering I can only interpret by eliminating impossible interpretations. I'm guessing that the target is aged for hours per witch level, and you maintain the benefits for hours per intelligence modifier. It could be written much more clearly.