[theptip]

> software engineers don't have the luxury of doing a diagnostic

These are called "spikes" in the agile community (no idea why), and "prototypes" elsewhere.

If you feel that the error bars are too wide on your estimate, you should build the minimum prototype required to reduce the uncertainty to tolerable levels.

I like to schedule these at least a sprint prior to kicking off the main task, so that you can benefit from the improved estimate accuracy when actually scheduling the thing.