BLAST+ memory hog with subject FASTA and XML output

We noticed a major memory problem running NCBI BLAST+ with XML output using a FASTA subject (consuming loads of swap space then getting killed). This doesn't happen with tabular output, nor if using a BLAST database:

Memory and CPU usage (until killed by OS)

Missing feature locations in GenBank "with parts"

My last blog post was on a problem with missing NCBI GenBank feature location information for trans-spliced genes when using GenBank 'with parts'. That was fixed, but while using EFetch a colleague just stumbled over something possibly related where the location is given as just a question mark. This took a little digging to understand...