I second all the ones who said to buy the fast track pass. Easy, worry-less, cheap enough. No brainer here, rather than trial and errors. It's perfect for Friday departures or holidays/special event days.
Here is the link
https://www.gva.ch/en/Site/Passagers.../Priority-Lane
Dont' worry too much about the entry time, it's just for their stats. Never had an issue.