But are they ever going to admit that they have no idea and accept your estimate on face without playing BS mind games? Probably not. But for some reason that doesn't stop them from trying.

I've never seen someone try and do this with a home contractor.

It might also be that they’re surprised at the complexity and want to know more. For this reason, the important part of an estimate isn’t the number. Its the task-breakdown and the identification of risk.

In most cases, people who ask "Does it really take that long?" are giving you their first emotional reaction and haven't actually thought it through deep enough to decide to manipulate you. They're upset and they want to make sure that they understood you right - which is a thing people often do when they get bad news, and I cannot blame them: if you get upset about something, at least make sure you really should be upset.

So, you should react either in a spock-like "stupid rational", giving no thought to what they might be implying whatsoever with a simple "yes", or, even better, in an emotionally-aware rational way: acknowledge their emotions and offer options. There are always options and trade-offs, they just need to be clearly communicated. Not "OK, I'll do it in three days instead of five", but "I'll can do it in three days with prototype quality so we can test it out, but it will be buggy as hell, not fit for production, and you should document it". I've never had a manager who had a problem with that, and I despite how popular horror stories are, I really doubt that there's a lot of them out there.

Your manager cares about the product, he's emotionally invested in it and wants everything to go as fast as possible - it's not a bad thing! It's only bad if you view his disappointment as your fault - but it's not. It's just how things are. As a developer, you're often a messenger bringing bad news. There's no way around it, and you have to learn to deliver bad news for people. And separate these bad news from you and your professional self-confidence.

If he was emotionally invested in the product, wanting everything to go as fast as possible is not necessarily a good thing. I can make things go as fast as possible, but then the questions become no unit tests? no integration tests? spaghetti code?

And this isn't a response from a few go around either. This is often the first thing that comes out of their mouth, right at the beginning of the project.

What happens is as follows:

1) Your manager has software development background and uses it as a superiority contest to show how much better they are than you. His lack of awareness regarding variable skill level or lack of knowledge of an existing system seems to factor little into the question. So one could argue the manager could be more empathetic in this case.

2) Your manager knows nothing about software development and really has no business asking such questions in a condescending manner. So they either pretend to know or they promised someone higher up the chain even though they had no idea, but were scarred to say so, thus the cycle has completed.

3) Your manager has a calm, rational head and accepts your estimate, your explanations, and has a good understanding of the product to negotiate with you in terms of requirements without getting emotional. The manager trusts understands that your estimate is, more than likely, not going to be accurate but accepts the changing winds and doesn't hold you to the fire.

I totally agree its better to be explicit. Which is why it matters to avoid overly emotional reactions and accept what people tell you so hand waving can be avoided.

But this is more of a prevailing problem in software requirements in general. It's rare that developers get projects with clear ideas on what needs to be done because of the ignorance or unknowns in questions that need to be asked in order to deliver a product. Often the developer has to decide, and when they do and its wrong, then they have to fix whatever they decided because no one explained, or bothered to explain, how something was supposed to work in the first place.

I'm surprised that you haven't. I've certainly seen the same kind of thing happen, though admittedly it is usually based on cost rather than time. Ultimately, though, the discussion was the client disbelieving a high effort estimate.

Is it?

Questions have built in assumptions and implications. Most questions don't have enough to be of concern, but some questions definitely imply things beyond the question itself. When asked 'Does it all take that long?', many hear an implied 'Make it not take so long.' command. It is not implied all the time, but it is implied often enough. This does not mean someone has low self-confidence or needs therapy.

If you go from "my boss gave me a command" to "I must execute the command and not question it" without exercising independent judgement, then I would assert that you do have low self-confidence. Whether someone needs therapy is a deeper question that we should be hesitant to answer for another person. But therapy was tremendously helpful for me in realising how my personal and professional life were held back by my reluctance to trust my own judgement or endure the discomfort that can come with honest, respectful, collaborative confrontation.

I should make explicit: Part of trusting ones own judgement is also being willing to say, “I don’t have enough knowledge/experience to make a trustworthy judgement here.”