item numbers should display even for single item manuscripts

[holfordm]

Often it makes sense for item numbers (the n attribute on msItem) not to display if there is only one item, but for multi-part manuscripts with continuous item numbering (a common cataloguing practice), it can create confusing results - for example, https://medieval.bodleian.ox.ac.uk/catalog/manuscript_10109 where items 3 and 4 have numbers but 1 and 2 do not. There are several other examples in the Merton manuscripts.

[andrew-morrison]

Are you saying you'd like @n to always display whenever the msItem is inside a part? And then make the rule for cataloguers that they shouldn't add @n at all, unless works are to be numbered sequentially across all parts, or if there are multiple numbered works in one part. There might be some tidying up of existing records to do in that case (e.g. MS. Arch. Selden. B. 8).

Or are you asking for the XSLT to look ahead and decide whether to display the @n depending on whether the next msItem in the next part is numbered next sequentially (and backwards too, so last one displays.) This might be difficult to implement as there are a lot of scenarios to anticipate (both different hierarchies and different numbering schemes.)