However, you have the issue of people being initially turned off by this new plastic, considering it potentially incompatible. LEGO could easily solve this by shoehorning it several years ahead of schedule, then letting the cat out of the bag when 2030 hits.
Would it solve all the problems? no. But it would solve a lot of them, including why teal is suddenly a different colour - different plastic.
Interestingly enough, LEGO prefers to call dark green 'Earth Green' now, and the standard colour of green is Dark Green instead. Granted, most of the AFOL community has not put up with the change, but considering what LEGO decides to rebrand its colours as, I wouldn't be too surprised if they said the cape piece was a certain name, and the LEGO community members who don't have the piece adopt LEGO's name without a question. Of course we'l all have to wait until some Bionicle fanatic (like us) gets the set and compares the two.
But even if there's a new constraction line in 2018, I don't see how a returning colour would suddenly prove its existence.