Coppell said: “I don’t think there is any advantage or disadvantage in changing management.
“There does seem to be an immediate positive effect but then it returns to normal.
“In the short-term it can change results but long-term there is no great turnaround.
“I do not know what has gone on at Charlton or the reasons why so it is difficult to make a judgment on the decision.
“We’ll leave it to them. It is not our problem.”