Seems quite useful, allowing the developer to guide the garbage collector into the right direction by carefully placing statements to tell the garbage collector

Seems quite useful, allowing the developer to guide the garbage collector into the right direction by carefully placing statements to tell the garbage collector when it is (not) ok to run. But make sure to add some comments describing the purpose of those statements, and how to profile your code to check whether it's still working correctly. Don't want to accidentally stop garbage collection altogether, either.