I have encountered a problem many times over the past week – very similar to a thread posted in the engineer forums “pvp bug”. You use grenade kit skills but they do not show explosion graphics on the ground or do any damage to the enemy. There are no “missed” or “invulnerable” type of messages or anything. The grenades just… disappear!! Yet the skills go on cooldown.
The thread in the engineer forum states that it is only against elementalists but I swear this happened to me against a mesmer tonight – I don’t think there was an elementalist around. This is a pretty terrible bug for engineers playing pvp!