It tells the personal stories of young people struggling to say on the right side of the line between success and failure. (powells.com)
Two further pieces of data must be determined: to which comb line was the unknown laser light closest and on which side of the line? (scientificamerican.com)
It only rarely became an actual problem, but it put the game on the wrong side of the line between challenging and frustrating when it came up. (theswitcheffect.net)