As Chris rightly pointed out, I'd forgotten about these types of charts being used in Gygax's S3: Expedition to the Barrier Peaks. Here they are, for comparison purposes:
Though the system is largely the same, the 1980 charts have been tidied up a bit and clarified versus the Ward and Jaquet 1978 GW charts. I think it's interesting that though Metamorphosis Alpha (1976) is clearly the inspiration to both later TSR publications, the artifact deciphering system is different. MA uses a percentile system: cross referencing the Leadership Potential character ability vs. the item's complexity yields a percent chance of success.The more I think about it, the more I like the later system vs. the percentile system, for the potential additional (minor, but fun) role playing it affords, or at least seems to encourage more, even with the the speed and simplicity of the d% method. I've never played the 2nd through 6th(!) editions of Gamma World and wonder if the artifact deciphering rules were ever changed "back" to the percentile system.
Another approach are saving throws - Akrasia's excellent article "Thieves and Tasks" in Knockspell #2 discussed these as 'a kind of general task resolution system' which could easily be applied to resolving artifact deciphering. Matthew at The Wheel of Samsara proposed something like this using an INT Save with modifiers based on the item's complexity and with a short list of results to consult.
Update: Just to add for those that might play Mutant Future but who've never owned or played Gamma World: Considering MF has three levels of artifact complexity just like 1e GW, one could easily use the GW charts there if they wanted to (if this wasn't obvious). See previous post here...
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