[QUOTE=sgoetzin;Grade is determined by the Heiland SplitGrade which is 100% accurate
I do not mean to sound disrespectful, but I find it a bit strange that you should trust a machine or whatever one of them is. Your good old fashioned eyes will tell you weather you have got the grade right or wrong.
I use Ilford MG4 Matt with great success, deep blacks and fine whites. Both achieved in almost all developers I have used, including Ilford Warmtone. Other Photographers here on APUG, whos work I have seen printed on Iford MG4 and developed in Ilfords Warmtone(and coldtone), literally sing. with the most exsquisite blacks you will ever see, and tones right through the range, right up to the brightest highlight. Leon Taylors work comes to mind.
Chuck your gizmo in the bin, or at least trust it with caution, go back in the darkroom with a box of fresh paper. Do a test strip and work from there, using you heart and eyes as your tools to determine exposure.
Subtract your dry down factor, and I am sure that you will come out of the darkroom singing and dancing.