You're clearly not playing more demanding games man.
And no, it has nothing to do with testing methodology. I follow user performance reports just as much as benchmarks and a 970 is just about *always* ahead of a 780, usually by a clear margin. Plus a 970 can be overclocked more. And I'm talking about real game performance, not artificial benchmarks.
And as a 970 owner with a decent OC, I can assure you that it's nowhere near good enough for 1440p/60fps at max settings in everything. In *most* graphics-heavy games, my card is only about good enough for 1080p/60fps at high-ultra(mostly ultra to be fair). It seriously does take a 980Ti to do what you're claiming you can do.
You're either lying, exaggerating or are mistaken. You do not have a magic GTX 780.
Just to be clear I'm not making a case of the overall suitability of a 780 at 1440p these days - none the less there is a huge gulf in performance across the range on out the box performance - something like 20% from an early A1 to one of the last B1s and what might be ok with one 780 might fall flat on its face on another.
Regarding my own setup - one aspect here is that I'm running G-Sync which makes it a lot more tolerable when you are getting drops just below 60fps - otherwise the card would have been replaced by now as it is certainly stretched at 1440p.
To put a certain amount of perspective on it a quote from one review (this was soon after release so the 290X stuff isn't so true any more - though does put some perspective on just how far the 290X has come):
The GTX 780 GHz Edition has big gains over the stock card in Battlefield 4 that essentially puts it on par with the GTX 780 Ti, give or take a couple of frames. At 2,560 x 1,440 and 5,760 x 1,080 it's 13 and 17 percent quicker than the vanilla GTX 780 and surpasses the AMD R9 290X, and even Sapphire's overclocked one.
My out the box boost is a little higher than their review card - in general over a range of games I'm averaging somewhere about 18% over a "vanilla" 780 which makes quite a difference when you are talking 1440p performance - where a normal 780 would be getting say 45fps I'm looking at more like 53fps which when coupled with G-Sync is pretty much indistinguishable from 60fps. Add to that a fairly hefty overclock again and the card is still pretty much hanging in there at 1440p with all the settings turned up though in truth I generally drop the AA down to FXAA or similar to give myself more of a buffer.
I do play many recent demanding games - though there are 1-2 I've not played like The Witched 3 and Far Cry: Primal which might change my opinion at 1440p in those games maybe - but stuff like GTA V, SWBF, etc. all run fine - I gave Everybody's gone to the Rapture a whirl with max settings and sure the 970 was a couple of FPS ahead (and I couldn't really catch it up quite even with overclocking) and the 780 was dropping to 30fps in the demanding bits - but a 980ti was only at ~38fps in the same scenes heh.
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