I've also been trying to replicate the IUI curve with the midnite classic and have come to the conclusion that it's not necessary. It's just a convenient curve for forklift batts because you can charge fast and get nicely mixed electrolyte at the end of the charge. It's also easier to determine when end of charge is reached, because you can just watch the voltage, and when it stops rising you're done. But it's not the only way to charge a forklift batt, and I think it would be detrimental to the health of the batt to follow that curve every day in an RE system when the battery is not actually discharged much at all. Unnecessary stress and voltages when the batt could very well be quite full already (> 80%).
my batteries should be going more or less 50 to 55% every day ... not 80%... yep reading the manual of tristar mppt60 it seems that the it go from from bulk to equalize...
My fears are that the batts would never reach 100% charge and then sulfation, if they are made to reach 2.65v every day and i will only get them up to 2.35..
but these last weeks no sun... at all

thanks for the answer.