The 290x wasn't faster than a 780ti, Yes it aged better but AMD released the Hawaii cards to outperform the original Titan & 780, The 780ti & Titan Black were waiting in the wings, The 780ti released within a couple of weeks of the 290x retaking the performance crown with the Titan Black coming after to ensure the Titan branding remained on top.
Up until the Titan released I think the 7970 GHZ was the top card, First the 7970, Then the 680 and then the 7970 GHZ until the original Titan appeared.
I just googled the dates and the 7970 GHZ released on June 22nd 2012 & held the crown until the Titan appeared on May 23rd 2013. That was AMD's last untouchable and it held the crown for 9 or 10 months..