[insulanus]

I think they mean the exact opposite of "coincidental", in the sense of "hmm... is this a coincidence" (no, it isn't)

[DannyBee]

I get that, but i guess i don't understand what there is to be guessing at at all.

I think it's been pretty straightforward that Chris joined Google and started this project. You don't have to wonder if that's a coincidence, that's what he's happy to say happened.