Hi PC,
Yes, it is reliable and, as I said, it is often used.
To be more specific, the leading edge of the XOR gate produces a narrow pulse which has a leading edge coincident with the point of change of the input square wave, plus the propagation delay of the XOR gate.
The pulse length of the XOR gate output can be extended by introducing more delay to the signal path of one of the XOR gate inputs. This can be done with a resistor and capacitor at a Schmitt trigger gate input.
In spite of the longer pulse the leading edge of the XOR gate output will still be just as coincident with a change in the input wave form.
This circuit is often use in frequency doubling, the output from the XOR gate having twice the frequency of the input waveform.
spec
(our posts crossed AK)