I've got a WW flour / bread flour recipe that works for me. It's got 50g vegetable oil per loaf, which works out to about 10%. After a few days on the counter, it's still relatively moist, I assume due to the oil.
I've got another recipe for rye bread, which I really like. It's basic ingredients (flour/water/yeast/salt), and for the first couple of days, it's terrific. But by day 4 (if it lasts that long), it's starting to get terribly dry. I was wondering if adding some oil might help things. Is there any good reason not to try this? Anything catastrophic that oil can do to a loaf that doesn't call for it?
... 1.5% olive oil to my bread - used to add 3% in the past. It makes the crumb softer and better in my opinion
Both fat and sugar help contribute to a more tender (but generally more fine) crumb that will stay tender longer than without.
Experiment with both in low %'s (~2 to 8%) and see what gets you what you like...
I'll add some oil to my next loaf and see how it goes. Thanks!