Don't worry too much about some guy running 1.7s. Worry about being as fast/consistent as you can, AND cutting a good light. You can easily win events running 2s if you're consistent, and good at the light. At these times, even a slight "sleep" will cost you even if you're capable of running 1.5s. All it takes is one slip-up for a fast car to not win an event.
Also, regarding people like Frank running 1.5s. If you watch the vids, you'll see that the track conditions are pretty far from your typical "no prep" track. There's a ton of sticky icky from everyone running the goo on their tires, to the point it's hard to call it no prep at this point. This has been a trend as of late and a huge reason you're seeing these faster times.
Nobody is running that fast on rough, dusty tracks and dry tires, I can tell you that for certain. Low 2s are more typical of the faster cars for that kind of condition. That being said, while the current trend is getting the car as light as allowed, and putting tons of goo on the tires, another direction is to add more power along with some weight to aid in traction. A car like that is likely to be more consistently getting A to B.