Another thought on Lightroom crashes

I sometimes feel like a Lightroom bonehead. I try to help people, and often make stupid mistakes. I don't understand why Lightroom crashes like it does. However, I recently thought I had lost some images from a catalog. It was a trip my wife and I took to Alaska several years ago. I decided to create a separate catalog and start editing them again. Then I decided to import that catalog into my main catalog. I hadn't experienced crashes in my main catalog for a long time. After I merged the two catalogs, I realized that the images were already there, same filenames, and I had the option checked to not import duplicate images. I thought this was rather strange that I now had two sets of the same images in the same catalog, but decided that I would keep them and see what happened. The images were about 10 years old and I wanted to redo them using the new Lightroom and the improved features. Well, Lightroom crashed twice in one day. That had not happened to me before. I decided to remove the other Alaska folder and just keep the one that I had now just imported. The crashes have stopped. So that experience is causing me to wonder if maybe one of the causes of crashes is merging catalogs and duplicating images in the same catalog. It's just a thought, no real evidence, but perhaps a clue of where a problem could (I stress COULD) exist.