Well you've answered your own question really. There are two different thoughts on pitching lager yeast. One camp says pitch at around alle temps, let it get fermenting and then cool down. The rationale is that you get a good healthy fermentation going.
The other camp says pitch at lager fermentation temps, as once the yeast gets going you will have difficulty getting the wort down to your desired temperature. It might take 24-48 hours to get the wort down to lager temps, and by this time it might have already fermented out by 50% or maybe more and the beer would lack a clean lager taste. When following this method it pays to pitch a BIG starter and aerate well.
Myself, I pitch at lager temps. I don't brew a lot of lagers, but a few of my first attempts were pitched around 18C-20C, and I wasn't able to get the temps down to 10C before it had virtually finished fermenting.
Oh, then there is some crazy idiot that advocates pitching even warmer than ale temps, but he truly is on his own with that opinion.
My suggestion is try both methods and see what works for you. Or if you want to be cautious, just pitch at lager fermentation temps.
Cheers
MAH