Ok, I tried this today but I did two things differently: I only used chicken breast and I only marinated for 9 hours. Apart from that I followed the recipe exactly.
My verdict? Overrated. The chicken breast came out beautiful looking, moist and tender but the taste didn't blow me away, really. There's something about it that I don't like very much - maybe it's the mustard oil which I did temper as some members have advised and as I saw on some blogs about traditional indian cuisine. I think that CBM's/Mick's Tikka using Patak's pastes or CA's Tikka made from scratch are both better. Blade1212's, too, representing the 'no-yoghurt' camp. Not much, but still better. Yes, I am mixing up Tandoori and Tikka but to me it's almost the same. Call me an idiot, if you want.
I won't make this again.