While it doesn't look like he was exactly following the yellow line, he is pretty darn close to it when the photo was taken.
It looks like there may not be an aircraft parked at the next gate over (the gates at TBIT are quite close together for the airplane sizes that park there, hence towing in and out). So maybe he had some leeway on towing in. Although it occurs to me - do we know if that's a tow-in or a pushback?
That dashed white line does look funny though! A few too many beers before painting it, perhaps.
I'm watching Jeopardy. The category is worst Madonna songs. "This one from 1987 is terrible".