I would hope that Lexus, in all it's automotive wisdom, would have designed the fuel pump to avoid damage should the fuel tank run empty. :( ........... but then again why is the paint so soft you have to wash and dry it with super special fabric material!! <_<
Responsible Lexus drivers don't run their tanks down to the fumes.
As for drying, I use the touchless car wash and then go for a 100 MPH (no drifting) run and it dries everything except the trunk lid and rear bumper. For that I use a waffle weave microfiber drying towel. In 2 1/2 years I haven't seen any evidence of soft paint and have no scratches, rock chips, or swirl marks. I think the Zaino CS helps in that department too.