I'm constantly needing to go back and uncheck this box when really there should be an option to change the default. (at least that's my thought)
Add a weldment to your part
2018 SOLIDWORKS Help - Weldments
Merge result is then unchecked
You may wish to uncheck the create derived configurations option and read up on the other options
By the way you can save this a part template, so it's already set up
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