As I recall, TNE used d20 below (stat+skill)*difficulty factor rather than d20+stat+skill above difficulty factor. The key difference here would be that in TNE (and other GDW games), difficulty is expressed as a multiplier of the normal chance of success, whereas it's a linear thing in 3e. As an aside, this scheme means that the skill level matters *less* when trying to do difficult stuff. Also, the first game *I'm* aware of using a similar mechanic is James Bond (though it used a d100 instead of d20, and the "stat" part of the formula was often the average of two stats and in one case included another skill) which dates back to 1983. Note: I'm not saying it was the first, just that it's the first that I am aware of.S'mon said:
I have Traveller: The New Era (c) 1993 GDW, when I got the 3e PHB back in 2000 I immediately noticed that 3e's d20 task resolution system was almost exactly the same as that in TNE's 7 year old rules. It wouldn't surprise me that there was some 'inspiration' from TNE/Twilight 2000 in 3e's rules, although independent creation is possible too.
I think that a more immediate inspiration for 3e's task resolution can be found in Ars Magica, which uses d10+stat+skill vs. difficulty number. The first edition of Ars Magica was written by Mark Rein-dot-Hagen and one Jonathan Tweet. Come to think of it, a similar task resolution mechanic was used in Rolemaster (except with open-ended d100s and tons of other modifiers), and RM was first published in 1980 (again, it might have been used before that but RM is the oldest RPG I recognize that uses that mechanic).