I watched the video they uploaded and it looks to me like the titan core clock is jumping all over the place, im guessing that is why.
!
the memory is set at either 3005 (which could be fine as that is basically stock) or 3386... which is not +350
they also don't appear to be running a custom fan profile, because they are letting the card get quite hot, which isn't entirely necessary for benching
also, over overclocking the memory impacts on GPU OC, so whilst they might have found the biggest 2 numbers they could find on the + scales, it's not necessarily the best OC performance wise the card is capable of
on mine for example, depending on benchmark, I can do +100 +325 for best results in Heaven... or for 3D mark I can do +135 +275
I can set my card to +150 +350, but I get lower scores on benches
I don't have tomb raider, so I can't run the it at similar specs to compare, but their firestrike score seems low for the specs and setup they claim to be running on, to the tune of about 300-400 points, as I get 5252 on CPU and GPU clocks much lower than they have, and again their screenshots don't match their bar graph scores