Hi steevo,
Just to clarify, Im not suggesting that removing all the strings will damage the neck in any way. Obvioulsy sometimes its neccesary to remove all the strings (in order to clean the neck etc). This will however have an impact on the tension pulling on the neck and the trem springs (as will removing a single string at a time but to a lesser extent) which in turn affects the neck angle, string height, bridge angle and intonation. This may or may not lead to adjustment of the truss rod, saddle height and bridge angle etc when all the strings are replaced
My point was that using the method described above tends to keep all the other adjustments to a minimum by putting the least amount of change in tension and stress on the neck and bridge, therefore potentially reducing your workload further down the line.
I've found over the years that for quick, easy string changes the B E G D E A method works great. I also tune this way on every guitar. Just my opinion so take it for whats its worth