If that’s your goal then you could split your PDFs into RTFs
- convert PDF to RTF in DEVONthink
- remove unnecessary stuff from RTF
- use Script: Split RTF(D) at Font Sizes
The conversion from PDF to RTF is not perfect but it’s a nice way to make stuff easier readable. I don’t delete the PDF, it’s really only for reading on iPhone.
In cases where I want to keep the split RTFs (instead of deleting them after reading) I open the unsplit RTF in Nisus Writer and remove page numbers etc. via regex. It’s a bit more work but this way one can get quite good results.