Some very good points were made... Apologizes if my initial post was too vague, it will be narrowed down as you read.
Mistakes get made even by the most experienced eyes, and its unfortunate to hear situations where a signature is removed and later proven to be that same smith. I've heard some horror stories myself. But sword groups like the NBTHK and NTHK help us to be able to set a standard in this industry, the resale of a certified blade is no doubt easier and faster. Sales through the internet make us instinctively ask for paperwork since we are not able to examine the blade in hand, pictures can hide features that the eye would normally be able to catch. Chris hit the nail dead on regarding certification.
Alex, I would be careful with this, you pointed out that you know a dealer that does not like to put blades through Shinsa due to the expense and time required, I can sympathize with this because it is difficult as a dealer to hold up funds in an item for an extended period of time. This is why trust is needed and it is always best to deal with reputable dealers, even if they make mistakes they will own up to it in order to maintain their reputation. Just be careful who that dealer is though!
As collectors we all have different goals and interests but what I was really curious to know was the opinions and experiences of actually removing the Mei, I've never done so myself and I share my opinion close to Gary's. If an item is Gimei someone at some point in time did this for a reason and that remains the history of the item, now at this point in history I would feel bad to be the one making the final decision to alter this, something irreversible. I've had this opinion from when I first started collecting and I always though it would change as I evolved, but funny enough it has remained the same and I think it may be the Historian inside me and the appreciation of keeping things the way they were. I don't like to be the person making the decision to alter or modify the history of the blade. I've sold blades in the past that were Gimei and made my thoughts very clear to my clients, I always told them that if they insist I can point them in the direction for the alterations but I did not want to have direct involvement in the process. Good work is good work regardless of what on the Nakago. I know many of you might not agree and are eager to hit the "Post Reply" button, I am interested to hear your thoughts.