QA output created by 639
Initial state ...
one.one.one.keep4 PMID: 4.0.4
two.keep3 PMID: 3.0.3
keep1 PMID: 1.0.1
keep2 PMID: 2.0.2

Serial additions ...

d1 PMID: 1.1.1
keep1 PMID: 1.0.1
keep2 PMID: 2.0.2
one.d2 PMID: 2.1.2
one.one.d3 PMID: 3.1.3
one.one.d6 PMID: 6.1.6
one.one.d7 PMID: 7.1.7
one.one.d8 PMID: 8.1.8
one.one.one.keep4 PMID: 4.0.4
three.one.d5 PMID: 5.1.5
two.d4 PMID: 4.1.4
two.d9 PMID: 9.1.9
two.keep3 PMID: 3.0.3

Parallel additions ...

d1 PMID: 1.1.1
keep1 PMID: 1.0.1
keep2 PMID: 2.0.2
one.d2 PMID: 2.1.2
one.one.d3 PMID: 3.1.3
one.one.d6 PMID: 6.1.6
one.one.d7 PMID: 7.1.7
one.one.d8 PMID: 8.1.8
one.one.one.keep4 PMID: 4.0.4
three.one.d5 PMID: 5.1.5
two.d4 PMID: 4.1.4
two.d9 PMID: 9.1.9
two.keep3 PMID: 3.0.3