These messages are confusing because they do not change when the linker, or linker options change.
If a user launches a job with "cvm_nogc", it is confusing to have a line saying "Memory saved by GC", unless it is 0. Or it should be something like "Memory that could have been saved by GC".
Idem for linker="c|py", if that linker was actually used, there should be a line saying "memory that could have been saved by using the lazy linker" or something.
I think the first line should be the amount of memory actually used. Then, maybe, things that were used to lower memory usage. Then, clearly marked, things that were _not_ used, and how they would have affected memory usage.