SoxSexSax
Chieftain
Worker first is the correct start in 9/10 games.
Not if all of your games are multiplayer it isn't, well, not unless you want a 90% loss rate on Pangaea maps. In an online FFA, on the turn I finish my first (i.e. second with the starter) Quecha when playing as Capac, I check the power graph. If my neighbour has gone worker first...cya!

It's debatably true for SP but I'd need to see serious studying of numbers done to come up with anything like a definitive X% of the time statement. Is the extra turns of having a worker when you start with no worker techs (for instance Spain, who start with fishing and mysticism) really worth the exp a warrior can get if it is fortunate with the RNG? He could survive all the way to Rifling, be upgraded and capture 5 cities single-handed! Unlikely, true, but perfectly possible, which makes analysing the "best" start practically IMpossible.