From the article: if you’re a holder of Greek bonds right now, you have three choices... 1. You can do nothing, and hope that Greece pays you in full and on time. (and other stuff)... The first option is by far the most interesting. No one has come out and said that Greece is going to default on bondholders who don’t exchange their bonds;
IE, the aim is to threaten and arm-twisted big banks into exchanging their bonds without any formal default happening. If we're going by a "gold standard", when Greece actually misses a payment on its bonds, then it will have defaulted. Until then, this is negotiation.
Further from the article: "Is it possible for other bondholders — those who haven’t had their arms twisted — to free-ride on the back of this deal and continue to get paid in full? I suspect that it probably is. Which is one reason why this Greek restructuring won’t be the last."
Again, nothing has happen to the non-big-bank holders. Indeed, they get a convenient free-ride.