If I want to add a comment about a code block, it makes zero sense for the comment to lob up right in the middle of the code block being commented on.

 

Current (silly) way 

var a = b + c

Comment: Why can't all of this be done in a single line statement.

var d = a + e + f

var g = d + h + i

 

Best way 

Comment: Why can't all of this be done in a single line statement.

var a = b + c

var d = a + e + f

var g = d + h + i

 

I always add my comment to the line above so I don't destroy readability, but someone has just pointed out to me that my comments are visually linked to the incorrect line.