do -10% mitigators mean -90% is the limit cap for "Not Disadvantage" advantages?

[Plane]

I remember seeing Mute (Substantial Only -10%) mitigator in GURPS Horror for the Poltergeist...

whereas Fantasy uses a "Not Mute" advantage to counteract it.

A -10% mitigator (limitation on disadvantage) would be like having a -90% limitation on an advantage which removes a disadvantage, right?

In that case it seems like it's not subject to the usual -80% since you're not actually making add-on abilities cheaper, but rather, making subtractive abilities less valuable?

Since ANY situation where a disadvantage won't apply is valuable, whatever the -% is should not reduce the advantage to 0 points though I'm thinking, since it's value should round up. Meaning that the disadvantage as a collective idea (folding in Not Mute as a mitigator to Mute) should always be worth 1 point fewer if there's a mitigator?

[Anaraxes]

-80% isn't a cap for an individual limitation. It's a cap on the net value allowed after you've done the math to combine all the modifiers together (whether additive or multiplicative). Basically just a easy rule of thumb to try and weed out loophole abuse and highly distorted ability builds.

It's often used as forum shorthand for "almost entirely useless", but -80% isn't always the right value to use for that, either.

[AlexanderHowl]

For example, you could have No Mute (Substantial Only, -10%) [22] as an advantage. The No Mute advantage has no inherent modifiers, it is just buying off a disadvantage that possesses a modifier, so you could give it up to -80% in limitations. For example, a character could take No Mute (Accessibility, Only Children, -10%; Accessibility, Only at Night, -20%; Costs FP, 10 FP/minute, -50%) [5] to represent a ghost that can speak to children during the night with great difficulty. Of course, it may be cheaper and simpler to just change Mute (Accessibility, Adults Only, -10%) [-22] from Mute (Substantial Only, -10%) [-22] for that ghost only.

[Plane]

Originally Posted by Anaraxes

-80% isn't a cap for an individual limitation. It's a cap on the net value allowed after you've done the math to combine all the modifiers together (whether additive or multiplicative)

Yes I know, that's what I'm referring to.

A -10% mitigator on a disadvantage, if represented as a "Not Disadvantage" advantage, is basically a -90% limitation on it.

Originally Posted by AlexanderHowl

For example, you could have No Mute (Substantial Only, -10%) [22] as an advantage. The No Mute advantage has no inherent modifiers, it is just buying off a disadvantage that possesses a modifier, so you could give it up to -80% in limitations. For example, a character could take No Mute (Accessibility, Only Children, -10%; Accessibility, Only at Night, -20%; Costs FP, 10 FP/minute, -50%) [5] to represent a ghost that can speak to children during the night with great difficulty. Of course, it may be cheaper and simpler to just change Mute (Accessibility, Adults Only, -10%) [-22] from Mute (Substantial Only, -10%) [-22] for that ghost only.

No Mute (Substantial Only) would I guess mean "ghosts can't hear me unless they turn substantial". That could actually be advantageous at times to prevent eavesdropping but bad if you want ghosts to hear you.

Poltergeists have the opposite since their Mute (Substantial Only) is basically like taking No Mute (Insubstantial Only) where only other ghosts can hear them, which is beneficial in preventing mortals from eavesdropping, but bad if you want to communicate with mortals.

Since "No Mute" (built in talking ability) presumably applies to both substantial/insubstantial targets equall by default, I'm not exactly sure how you'd go about buying a 'selective' version to allow switching between one or the other or both at will for extra privacy options...

I've seen both of these in PU4
"Affects Substantial, Selective"
"Affects Insubstantial, Selective"

The net effect at the end seems to be the same, the only difference being where your starting point of operations was:

A) AffInSel would be for abilities that don't inherently affect insubstantial (like making innate attacks as a substantial char)

B) AffSubSel would be for abilities that don't inherently affect subtantial (like making innate attacks as insubstantial char)

If you have something which inherently already affects both (ie speaking and they can hear you) then would you just take "Selective Effect" and not worry about pairing it with "affects X" versions?