Guys, try to think out of the box. Of course there is risk in crypto and in ICOs, but look at what they are claiming: https://tachain.io/InvestmentOptions.pdf

They are not saying their token can not decrease in value or something like that. They just say that they are ready to exchange the SAME amount of ETH/BTC invested into the SAME amount of tokens you receive. It is a buy back guarantee, if after one year you are not satisfied with project progress or with token performance.

It is not just a marketing move.

Again of course it freezes your ETH/BTC for some time, the same as you would simply HODL it. Moreover, it is just an option - you can still invest as in any other ICO with some bonus. I do not see any "underwater stones" in such idea, it's indeed great and they are the first to offer such opportunity.

I personally understand your opinions, we all probably have lost some money in ICOs and it is hard to imagine a risk-free ICO, but try to think differently... There is nothing unrealstic in what they are saying.