No, I shouldn't think so Fundj, I'm just following what was posted about 2 years ago when I first started making it.
I can remember firstly cooking for 20 mins at 80C, then cooking further 20 mins after the culture was added, but then was told that wasn't necessary (either by Andi or Thermomixer, sorry I can't remember now and am unable to locate the post).
The new instructions were as above and I've been doing it that way since. If it's working for you at 10 mins then I can't see a problem. Andi would know, she's very knowledgable about this sort of stuff, though I haven't seen much of her recently.