Quote from yriel »@LEH : yes i keep it against Burn. I have understand i am wrong the first 50th times, thanks.
If you can help to me to understand why, thanks to you. If you just want to say me "it's obv you loose life" you can win some time and don't answer me. Yes i am probably wrong. Yes i know. That doesn't change the point i don't understand this point.
Yeah, sorry. Okay, lets look at basic examples.
Best case scenario: You cast TS. Opponent tapped out and reveals Boros Charm to you. You take Charm (You spend 1 card and to gain 2 virtual life.
Slightly worse scenario: You cast TS. Opponent is tapped out and reveals Lightning Bolt. You essentially paid 1 card to gain 1 virtual life.
Most common scenario: You cast TS and opponent fires of Burn spell(s) they had in had to your face (you take damage from their spell(s) and lose 2 life from your own TS).
Even the best case scenario is bad for us, that's why we SB it out.