"This place could just be a trick, right? A place that just says it's 1960." That's what Sans would expect someone to conclude, anyway, assuming they were human. Even though there's a lot going on, that could still be true, just with a lot of other caveats. ...But Sans isn't human, even if he's been stuffed into the body of one. This guy probably has the right idea. It's interesting that he'd have it, though. "Universe-hopping is a new one for me. Doesn't mean you're wrong, though. You got any tips?"

It really would be useful to have some tips, but really, Sans is also just plain curious.