I just watched his most recent interview in Mtv3 in Finnish and as a Wintersun fan I was delighted that, like in this Tuonela interview, he mentioned Wintersun a few times, but in the Mtv3 interview the questions were mostly about Nightwish, which is understandable since it's super mainstream in Finland, but it's clear that Wintersun still is super important to Kai and that warms my heart.
BTW. I'm legit regretting not buying a ticket to his show. I'm living nearby and I could've just went there but I didn't. Dammit. Oh well, I'm looking forward to seeing him performing with Wintersun soon enough.
it is really extraordinary, but it is not a talent nor a gift. It is hard work and doing it alot ! Like any classically trained musician can be put into an orchestra, open the music sheet and play perfectly.