At first it sounds proper rule and required on the other hand the rule is very strict and can be abuse easily. I will share some examples to clearify what i mean;
This rule only good when team have 5 decent players and all of them playing. Sometimes 3-4 min 1 or 2 players stay afk so this rule not let us farm other spots which is clearly unfair. Also some admins can abuse this rule and immideatly ban&kick player. My idea is we are all in same team so no need to behave like that. Some admins thinks same way, warn and wait if the action repeat or not But as i said since rule is strict some can ban immediatly even 1 hit.
Also mega creeps cause anther issue, as we all know some abilities let us kill mega early but sometimes its impossible to us kill mega creeps. Therefore 1 of the spots block farm so we are stay even more powerless. It happens me, i got devour ability and i pick sentinel 2 creep spot. Down part lvl6 satyr become mega so i just go other spot for devour lvl4 creep. Courage kick and ban me immediatly not even listen my defence. I dont say she was wrong but at least warn or listen why but since rule is strict she can prefer that way also.
In short my suggestion, 1st not let spawn mega creeps for 5min and 2nd soften rule when there are AFK players.