[hesitz]

I think the point is that it's harder to see what line number you want to jump to if you don't have line numbering on. . . .

[Scriptor]

Right, the alternative is to just sort of guess how much you need to ctrl-u/d or j and k to get to a specific line. Also, I guess it depends on screen size. I usually have plenty so the line numbers' usefulness outweighs the extra space required, at least for me.

[dionidium]

Yes, that's exactly my point