I don't overestimate, I am calling it a test case. Because they have done so in the past.
And MEA fools had to negotiate with them and release Mashood Azhar. Preventing such situation is one subject, in which government is perfect, handling such situation is a different job.
You do realise how absurd the case of Pakistan taking indians hostages is right? Especially in the scenario you envision. Blackmail? What kind of blackmail? Like wing commander Abhinandan lmao? And you're taking about a pre-emptive covert operation.. why the f will they do that? Even by use of proxy.. what will they achieve.
Note: MEA will have a field day in their diplomatic missions. And you don't compare potato with oranges.. kandhar hijack was not a covert operation of taking hostages from border villages and taking them back

, which is what you're saying.
2nd, even then the negotiation with Taliban wasn't led by MEA, but MHA.
We have experts in IB and other police forces for such roles. Weren't you the one who said multi-alignment and Foreign policy approach was because of IAS,IPS not IFS, Thinking MEA isn't a Beauracracy? Now handling of security situation is suddenly MEAs domain?


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Intelligence officers can be posted as IFS or other cadre on diplomatic missions. Doesn't make MEA into intelligence agency.
Now coming back from your wierd pov towards MEA..
If pakistan does that.. its a war. Period. And if you think they will try to "blackmail" away from public eyes.. then what kind of blackmail will it even be.
Maybe expand your test case.. give some details of what you envision the blackmail, taking hostages to look like from pak pov. Then, perhaps people here will be able to better articulate about such a scenario.
They are obviously trying to do espionage and terrorist attacks in the mainland. They've been doing it since ages. I already pointed out three challenges for the next scenario.