Actually I have answered this (oh wait a minute, forgot that you don't read the posts so they have to be repeated). There are several possibilities as to why it was important to know the circumference on the inside of the vessel. Since this was a very large fancy bath, it likely had some type of tile or decorative treatment on the inside as opposed to the elaborate engravings that were talked about for the outside. As such, the circumference on the inside would be very important for the builders putting the tiles on. Later on in the 1 Kings 7 passage, it talks about the volume of water that it contained when it was used for bathing (verse 26 - 'it contained two thousand baths'). Since this volume refers to measurements on the inside of the vessel, it is not surprising at all that a reference to an inside circumference is also made. Since the scripture reference doesn't tell us anything else, the above are just possibilities and there are others. However, for you to suggest that a surveyor wouldn't measure the inside circumference or that it was unimportant is nonsense. If anything, the inside circumference would be more important than the outside circumference. On the other hand, the diameter of the outside was important because that defines how big the structure is and thus what the space considerations were from an architectural perspective. You of course won't like my description of the possible reasons why those particular dimensions were selected but that won't be a surprise. It will be a surprise though if you answer the original question.
It's not a matter of me liking it or not, it is a matter of sticking to the point you brought up. It is a matter of whether what you are offering is conjecture, or not. And, of course, that is exactly what it is: conjecture. You are conjecturing reasons for believing the measurements are not in error, and you are conjecturing a mismatch between the two measurements to do it--which is, itself, erroneous. And it remains the case that your reasoning is extremely far-fetched. When you say you are measuring "round-about" something, you imply you're measuring along the outside. And even if that weren't so, you only need two people to pull a tape along the outside, and so that is what surveyors do. And the fact that the pot is decorated isn't going to deter you a bit. The pot isn't going to be decorated at the rim or the base, except in far-fetched land, where you seem to spend a good deal of your time.
Uh huh, and what fairy tale have you concocted to explain why, given that assumption, they didn't pull the tape for the diameter on the inside, as well?