This is an older thread but I do something similar though without changing configs. Maybe helpful / common knowledge again :)

* My pager is 'less'; I left that as-is.

* I pass the huge object to less in the same way: |x $huge_ref

* Then from within less, I use its option to bring up the Save-to-Logfile prompt: -o

I find that I send to the pager pretty regularly anyway, so this way I can save to a file more selectively. OP's idea is neat, too; this is just the way I like to do it.