I think that empty GC memory statistics can mislead users. In #1250 I create comment:

@adamsitnik I think that BenchmarkDotNet should not print information about GC if it doesn't run extra iteration. I mean this line:

GC:  0 0 0 0 0
Threading:  0 0 0

Extra iteration runs only when user adds MemoryDiagnoser or ThreadingDiagnoser. In other cases we shouldn't print these lines:

BenchmarkDotNet/src/BenchmarkDotNet/Engines/RunResults.cs

Lines 71 to 72 in 2ba3033

	outWriter.WriteLine(GCStats.ToOutputLine());
	outWriter.WriteLine(ThreadingStats.ToOutputLine());

Or even more precisely:
GC: 0 0 0 0 0 should print only with MemoryDiagnoser
Threading: 0 0 0 should print only with ThreadingDiagnoser

@adamsitnik What do you think?