The most preferred one would be an idle decent to FL 120 and then reducing to roughly 1500 fpm to achieve 250 kts or less at FL 100. This does depend on passenger (and overall cabin ) comfort and a/c limitations.
A 4000 fpm or more then 5 degrees nose down attitude would be uncomfortable. (somebody should tell Paris about that).
So my vote would go for a CDA.
This would mean not only a change in procedures in ATC but also in the training of pilots to follow those procedures.
Some ( my experience ) know the talk but don't walk the walk.
good luck with the study