You should try other things that force the brain to begin interpreting something again as new input; e.g., I have found success with changing the font, or the colour scheme, or looking at a diff rendition of a change, or looking at the file with less(1), or even reading the thing in reverse order, provoking a similarly new context where I see stuff I won't have seen staring at the editor for an hour previously. Another thing printing usually induces is that you simply stop looking at it for at least a few minutes before looking again, and a break often helps too!

Printing is obviously fine if you like doing that, but I've found there are lots of ways to shake yourself loose and more thoroughly review your own writing.