When drinking excessively, the Zone is usually reached when the human memory stops functioning as it should and the reflexes turn to sludge - Inane grinning will ensue and the reacher of the Zone will look very content with life and may require some assisstance in reaching the next pub!!
Try it for yourself:
Drink as much as you can!! If you remember going to the pub toilet and waking up in bed, then the Zone has been achieved!! Well done - you can now nurse your hangover until tonight when you will do it all again!!
If you remember eating the kebab, you've just wasted an evening testing this theory! Loser - Go out and do it all again until you achieve the goal!!