Commutative algebraists do it regularly. Complex analysts do it between the sheets. Complex analysts do it under a universal cover. Complex analysts do it with imaginary parts. Computer scientists do it depth-first.
Constructivists do it without excluding the middle.
Cosmologists do it in the first three minutes. Decision theorists do it optimally. Differential analysts do it in a degenerate case. Differential geometers do it on smooth contours. Differential geometers do it over and under the curves.