This can be annoying to say the least. When one attempts a strategy of feint-spamming, it's rudely interrupted. At this point you may consider it a point of conveniance for myself, only, but there is a logical precedent for my stance.
When a fluid deceptions double-feint occurs, the affect carries over until the next round should the enemy only get one attack in the following round. In essence, the feints are stacking in the case of a double-feint, wheras when a manual double-feint is attempted (as illustrated in the above log) the command is not allowed.
