I don't tune or run E85 in my Focus Titanium.
I'm talking about my SRT-4, sorry for the confusion.
If you are looking at LTFTs over time (as you drive the car every day) and make note of the values you see during certain operating conditions, it is easy to see a change in how much fuel the car is having to pull or add since the values don't jump around as much as the STFTs. As soon as the car is warmed up and at the first chance I can come to a stop, a quick glance tells me if things are ok or not ethanol content-wise.
WOT AFRs are monitored by my an AFR gauge, which is also on the column.
2015 F150 4x4 3.5 Ecoboost
2002 Camaro SS, new turbo install in progress...
2005 Neon SRT-4, Big wheel stage 3, E85