Towards the end of *All Good Things* when Picard convinces his crew to return to the scene of the anomaly: His point is that if he was right, then it would just be forming and they could stop it. When they got there they saw it starting and still quite small.

However, if all three ships had sent that pulse to that place and caused the anomaly which gets bigger as it goes back through time then surely they would not be able to see it when they went back as it started at the point Riker's enterprise buzzed it and it grew backwards in time.

Did I miss something?