Just recently came across this issue that unit modules were meant to be linked into a block file, but due to the large amount of small variations within the units, the designers wanted to have a base module to link into the unit file as well, such as:
Module A is linked to the Units file onto different stories. In the Units file, small variations are added to the base A, which eventually results in Unit A1, A2, etc. Similarly with Unit type B, C and so on. Eventually the Unit file was linked story-by story into the Block file.
Though from attribute management point of view such amount of hotlinks is not easy to manage, the designers preferred this solution to deal with the frequent design changes of the 30+ unit types. At the end of the linking process the problem was, that since the Units file already contained more than 20 hotlinks, the total number of links significantly increased in the master file, which caused slowness in general, for scheduling, for updating the links and so on. If the Units file could have been a single file without previously added links it would have been much easier to handle. To overcome this issue, a tiny, but very powerful function of the Publisher was activated: Break nested Hotlinks and Xrefs.
Whenever publishing modules – in this case every story that contains one unit type was published as a separate module -, using the embedding function under Options… allows us to get rid of the excess links. At the same time the designers could still use the Units file for doing their work, but the process was not hindered later either.
As an additional benefit, the published modules only need to be linked once into the further files (typical stories or directly into the block), whenever there is an update, they just publish again with a click and update the links.