If that's the spec these cards will barely outperform a 1080 Ti.
And why is that such a dismal prospect?
Seriously, Pascal was considered a big improvement over Maxwell, and yet the GTX 1080 wasn't massively faster than a GTX 980 Ti (which is about equal to a GTX 1070).
Not worth the money for 1080 Ti owners.
Of course not! And neither was the GTX 1080 worth the money for most GTX 980 Ti owners. I have one and didn't even consider a GTX 1080 Ti worth the money. Probably the GTX 1180 Ti will deliver the ~2x improvement I'm seeking.