Trial and error. That's how I learned what my strings can take. But .10 to .60? Seriously? Are you sure they're not .10 to .50? I run D'Addario heavy's on my acoustic, which are heavy as hell (heavy even for acoustic strings). And despite their heaviness, the low E string still isn't .60 (it's .59). Plus running off the (baseless) assumption that you are playing an electric, I highly doubt you have a .60 string.
There are a couple reasons why he would want to tune up guys. Making the guitar fit the singers vocal range better, getting a fuller sound (more tension = fuller sound, tuning the strings up a step would sound slightly different from simply capo-ing the second fret), taking care of fret buzz on guitars with that problem, etc.