Forgive my ignorance but what I understood is that new Muslims should have more kids away from their current environment and create new societies? is that what you mean?
Discussion
No, I mean that community building efforts should concentrate on a few groups that already show much potential rather than try to "save" all nominal muslims. The higher TFR in these groups is already a given because they are more religiously conservative.
So, when trying to "islamize" a culture or create a new one, efforts should be directed towards these groups because the others will either be a drag or because their cultural footprint will be so small, that they are not too strong a competing force.
That's an interesting premise...how are these groups with higher TFR identified? Is there a book from which this theory originates?
This is based on research by Kaufmann. Any muslim group that sees the sharia as an important guideline, would make this group of sustainable TFR. That is the given part. Not every subgroup, however, has the potential to be included in elite formation. That would be the second part.
The book is:
Shall the Religious Inherit the Earth? Demography and Politics in the Twenty-First Century.