Saint, although it says "Logged events can be restricted by contacts:" in the Prefences, when you click on Filter, it says in the opened window "The event viewer will display events for the following contacts:" so in fact we can't filter contacts whose events will be recorded to the Event Log file. I always wish we could, also in my opinion it must be like that
but what a pity it currently logs all contacts' events.
I advice you to uninstall Plus! (maybe together with all user settings) (make sure you saved them to preferences pack files before uninstalling), then reinstall it. If it still logs for that contact, try disabling all your scripts (if any). If it still logs for that contact, delete him from your list, sign out and then re add him. Also try disabling event logging for some time. Then reenable it.
Idle status doesn't belong to Plus!. Plus! only replaces the special away status of Messenger (which is set when contact appeared inactive for sometime) with Idle status. If Plus! wasn't installed, you would see them as away and you would never know that some of your contacts are idling actually.
People can force their Messenger to set their status to be changed to Idle (Away) with the help of some programs such as MessengerDiscovery. Also even if they don't have such programs they can always switch to Idle by locking their Windows session or switching to Screen saver mode. So the minimum delay is not 1 minute, it is the delay which you can set via Messenger options to change your status to Idle automatically.
The strange thing with your case is your contact doesn't change his status actually, but Plus! logs one event again and again. The time is always same for all the entries, even seconds.
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