First off I suppose i should own up to being team irelands lizardmen player for this year.
Unless Im mistaken at least 2 teams(singapore and sweden) are bring double blocks of saurus warriors.
The reason most dont use saurus is that they dont beat other things that are good in the 'etc meta' for want of a better description. Saurus tend to lose against all but the poorest monsterous beasts/inf/cav units, cant take other elite inf(white lions, beastigor, hammerers etc) either and get ruined by monsters due to thunderstomp.
skinks die just as easily to these threats as saurus but cost less and in skrox units cant be stomped. with krox they also hit back much harder against t4+ and the generally high armor save.
Double slann is for the flexibility in spells rather than anything else. it allows you to split the ld bubble( one is general one is bsb) which is vital for skink cloud armies. as for protection i just have mine hop between skink units.
Edit: as to the excellent players comment i cant speak for the rest but I'm no warhammer genius.
As for performance most lizard lists at the etc are designed to take bad matchups from the rest of the team and try for a draw. so most will average 50-60 points over the 6 games. As this is my first year if I get 50 I'll be happy.