Context is everything. To me, #.6-1.5 looks more like a recommended line range for a particular rod, rather than the gou (line size) number and the pound test, which I have never seen written in exactly that way. The only tables I have seen that give line size and pound test are clearly labeled so that you know which number is the line size and which is the pound test.

Many if not most JDM manufacturers give a recommended range of lines for each rod. A range of .6-1.5 is a reasonable range. Line size .6 could be 2.5 or 3 pounds test if nylon or fluorocarbon. Line size 1.5 would be 6 or 7 lbs test.