I think none did flat out broke me, but there were some that felt like a knife between the ribs.
One I certainly remember is when there was the Wat Tambor shard-bug and they asked us to report how many successful attempts we made on the node. It made me realize how painfully little they know about their own game if they needed to ask for data like this.
Then there was the very first day of the LSGeo. I think for me it ranks top.
Oh lets not forget the first version of the chPit with the synchronised attacks.
Gating r8 material behind GuildGP. Not Guildperformance, guildGP.
Oh when it leaked that LD is negotiating with cheaters despite the zero tolerance policy. That's a classic.
As I read this msg before posting it I think the LSgeo is the only one that is actually gameplay. The rest is the company.