Tips for yeast,
Oxengenate wort properly before pitching (the more in there the stronger the ferm)
Always pitch enough yeast
Lager yeasts quite often have a longer lag time that ales.
Make starter to ensure high cell count and proof yeast. (48 hrs before brew day is good)
I make starters at 15-18c .When they show activity i cool them slowly (2-8 hrs) to fermentation temp 10-12c lagers, 16-18c ales. At high krausen i pitch into wort at the same temp thus avoiding temp shock.
The problem with warm pitching is that your'e cooling the wort at the same time as the yeast is "waking up" to ferment. By waking the yeast in a starter first you are avoiding such a long lag time and you are pitching enough "active cells" to reduce lag time to acceptable limits (6-24 hrs).
Yeast consume o2 first during the lag phase (respiration) and reproduce then move on to the malt sugars etc (anerobic phase). This is when they start to produce co2/alcohols.
If you pitch a yeast and it starts fermenting straight (1-3 hrs) away chances are that there is not enough o2 in the wort for the yeast to grow it's numbers up and you will get a underattenuated finished beer.
Saflager, (sacromyces carlsbergenis) yeast isn't to bad as far as dried yeasts go and it's sweet spot is absolutley 12c. (liquid yeasts taste a whole lot better though and are purer)
So my suggestion for saflager (if you want to warm pitch) is to get the yeast going first then drop temp to appropriate ferm temp. (Probably the next day)
The reason i pitch at 10-12c is to avoid possible mutations of the lager yeast during the respiration phase into more fruity ale types of yeasts. Yeast that has reproduced at 10-12c will ferment at 10-12c no probs, yeast that reproduced at 18c could have probs at lower temps.
Any questions
SiMo