In what situations does an IRCC reconsideration request actually have a real chance of working?

Reconsideration requests tend to work best in fairly narrow situations: a clear administrative or clerical error in how the decision was processed, evidence that genuinely existed before the decision was made but was overlooked due to an obvious processing mistake, or new, decisive evidence that emerged very soon after the refusal and directly addresses the specific reason given for it. These are situations where something concrete went wrong or changed, not simply a disagreement with how the officer weighed the evidence.

Reconsideration is much less likely to succeed where the officer considered the relevant evidence properly and simply reached a conclusion the applicant disagrees with. In that situation, the more effective route is generally a formal appeal, where one is available, or judicial review, since those processes are actually designed to address a decision-maker's reasoning or legal correctness rather than simply asking the same office to take another look.

Because IRCC has complete discretion over whether to engage with a reconsideration request at all, framing it clearly around a specific, concrete problem — rather than a general request to "look again" — gives it the best realistic chance of a response.