It depends on the group you're making offspring with, but it collapses ethnic selection no matter what, and your descendants will won't be kin to you, it only makes sense as method if you aren't planning on investing anything into the offspring. If you reproduce with your group you're getting more then 50% of your genes in your offspring, therefore 50%< of your genes will be among furture generations and be consistently related to you, so you have fulfilled the purpose of reproduction. What you are advocating for isn't reproduction, it is selecting yourself out by wasting your energy on things that aren't your genetic interests, basically cuckolding yourself.