5 - 1 says that you win 1 time out of 5... not 1 time out of 6.
4BB + 4BB + 4BB + 4BB = 16BB
And you win 16BB
It's right =)
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Oops I thought that the 16BB was counting the 4BB loss.
At the end we are ending up with more than 1/5 of the pot from your stack...
I dont have time ot check now, but something is wrong ( or I could just me missing something. ) =)