Reduced Duration is the opposite of Extended Duration, since that is also called Increased Duration, RD could also be called Decreased Duration.
- -10% for 1/3 duration
- -15% for 1/6 duration
- -20% for 1/10 duration
- -25% for 1/20 duration
- -30% for 1/30 duration
- -35% for 1/60 duration
- -40% for 1/100 duration
Page 21 of GURPS Psionic Powers reprinted this.
still in the unofficial http://forums.sjgames.com/showpost.php?p=419825&postcount=5 as well:
- Maybe -10% for 1/3 duration, -15% for 1/6 duration, -20% for 1/10 duration, -25% for 1/20 duration, -30% for 1/30 duration, -35% for 1/60 duration, -40% for 1/100 duration, etc. About 1/3 off for going from minutes to seconds seems quite fair.
In GURPS Power-Ups 4 pg 4 under "Aura of Power" the "Reduced Duration, 1/60, Only after the target leaves the area" limitation is valued as -30% instead of the usual -35% for 1/60.
This indicates that "Only after target leaves the area" is either a +5% enhancement, or that this reduces the value of the RD limitation by 1/7
Kuroshima (one of the book writers) in http://forums.sjgames.com/showpost.php?p=1035661&postcount=5 wrote
- I must say that I regret not putting it as two modifiers. Bruno is right, it's +5% for the quality of life enhancement that once someone is blessed by the aura, you don't roll again, and the original duration will apply once they leave it.
- this value was determined in a long, three-way discussion between him, Kromm, and myself
- Aura + Area Effect means that the ability keeps firing off every second. That means that every person in the area has to make a HT roll every second until affected.
- what Toni wanted to do was to effectively remove that "then a second off", approximately doubling the amount of net time that the subjects were affected. As that was similar to doubling the duration, it was ruled that the net value should be equal to that of Reduced Duration 1/30 (instead of 1/60), a +5% difference.