> that tabular grain films exhaust fixer at the speed of light
That may be a misinterpretation. Tabular films contain much more iodide (indtead of bromide) which fixes harder. It is not uncommon to fix the film for 10 minutes. If you count the "freshness" of the fixer measuring the fixation time you may come to the conclusion of exhausted fixer. But it isn't. Tabular films simply need a longer time.
Yes but that is not apparent if you fix by time and temperature and only discover you have unfixed negs when you look at the film while drying or later.
If you fix by inspection and use two baths it is easier to ensure archival fixing.
Because I use plain hypo I normally need to fix the tabulars for more than ten minutes at 20C and in a multi tank it is easy to see which films are tabs.
You can stand tabs and non tabs 1:100 in Rodinal...