The 5d has two distinctly different periods of use. The value was dropped in 1924, and was re-introduced in 1930 with a new die and electros. The KGV watermark group is a Cooke inspiration, whereas Ash produced new electros for the post 1930 emanations.
There is some slight confusion with the KGV papers and perforations used on the Cooke electro.
As would be expected there is a normal progression from the line perforator to the new comb machines. However, the additional line perf entry is a very different stamp to it's earlier cousins. It was deliberately printed only on unsurfaced paper and specifically issued perf OS only. It was undoubtedly destined for the comb machine, but the results were too poor for issue. The printing languished for two years until absorbed by government departments.