Almot;
I applaud you on striving to set up your charging system the best you can.
IMHO, I do disagree with the concept that Deka is 'worse' because their table has wider ranges. I could achieve the table accuracy you seek by using their temp adjustment formula to arrive at an exact Voltage for any temperature in .1F increments, a very long table going up to 110F. I could do the same for Optima.
However, as I also explained, my MS SS 10 controller only has two charging Volts settings. When the weather is hot I use 14.1V, otherwise 14.4V. I cannot adjust in .2V increments. Plus, the temp comp is ambient. I actually screwed the controller to the inside of the box to get the best possible measurement. The box is an ice chest to help stabilize the temps. I guess I could use double sided tape and affix the controller in between the two Optimas to get a better reading.
We are both doing it right to the best of our capabilities. :)
HTH;
John