Background: I sometimes use Photo/Photo Merge/Panorama/Perspective to merge multiple photos of flat art or entire rolls of negatives (to make a contact sheet). Most of the time, this works perfectly, yielding images of fantastic resolution. However, sometimes when the art of negatives contain images of buidlings, the merge process goes wildly wrong, misinterpreting the image. An example is provided in the attached four images. 25, 26 and 27 are three partial shots of the same roll of film. 25-2-Pano is the panorama created using Photo Merge/Panorama?Perspective. You can see that it is wildly distorted by Lightroom's attempt to make a single image of the separate photos.
Suggestion: Please provide Lightroom photo merge with a fourth projection method that avoids this problem with flat art.
Possible method: I believe that Panorama/Perspective is often used to provide a single planar projection of multiple photos taken at substantially different angles. In the case of photographing flat art, the range of angles is very small. Perhaps a fourth projection option, perhaps called "Flat", could be based on "Perspective" but could limit the search for alignment to a very small range of camera angles. This might prevent wildly incorrect interpretations of the image.
For what it is worth: I found a workaround for the example contact print presented. This was to create a panorama of just two of the three images. This worked perfectly. This panorama was then merged with the third photo, and that worked perfectly too. So maybe there is an alternate way to do this. However, I knew in advance the order of the pictures so I could choose mergeable photos to start with.