Well, none of us were there so we're left to infer the context and tone with which the threat was made. The simple fact that a threat was made doesn't seem to be in doubt. Where did you read this guy merely told them to "be vigilant"? That's not what was written nor what I read. I will agree with you: not everyone should be an IP. However, having been an IP since 2004, I certainly understand the frustration that comes from being blamed for increasingly complex and broken process that an IP has no control over.
If another IP's gradesheet is overdue because he's been flying an ad-hoc schedule for several 12 hour days because they can't find anyone else to get a dozen crewmembers current before they leave for deployment next week while the network is down, don't expect me to wring my hands in worry that you'll take my cert away. I'm also not going to bag on the guy because he went home for dinner instead of writing me an essay in GTIMS.
An OG threatening me for his performance makes me think he's completely out of touch and expects all his IP have a predisposition for fcuking up. People tend to live up to or down to the expectations set for them. You are correct in saying a CC should set clear positive expectations and priorities. You are incorrect in saying a CC should set clear expectations, priorities, and make threats, especially over "paperwork". As an OG, If someone didn't do a gradesheet, you ask your SQ/CC to talk directly to that person. You don't personally threaten all the other IPs with being decertified.
That type of leadership style has been rode hard the last few years. If you think it's an acceptable one, let's have a look at the situation we presently find ourselves in.