Separating editions

It is my understanding that editions of a work are usually combined, but what if the content is significantly revised between editions?

Example: https://www.librarything.com/work/348674

The first edition (1907) of this hiking guide is almost a completely different text word-for-word from the 30th (2017), but are combined under the same work. Same institutional author and publisher with slight title variations.

I'm thinking about separating each edition and creating a new series, but interested in others' input.

With such a significant difference in content, the editions should be separated.

If you want inspiration, you could perhaps look at the series created for the similarly long-standing and oft-changed Joy of cooking.

After separating, it is advisable to create work relationships if 'is expanded version of' is applicable since they prevent someone from recombining later. Also, adding a disambiguation notice

Of course the first and 30th editions are quite different but how different are the first and second from each other? Are there maybe a few that have big changes with only slight differences in the ones between. If so it might be better to lump them into three or four works instead of creating 30 works.