I asked it to estimate a timeline for a feature in my hobby project and it confidently replied, “4.5 weeks to code completion”.
Less than 4 hours later, the feature was done. I asked it to compare this against its initial estimate and it replied, “Right on schedule!”
I have completely given up on using it to estimate anything that actually matters.
That's really useful for some tasks, like regurgitating code to perform a specific function, but it's basically useless for jobs like estimating schedules.