split grade printing - can it be done with only G5 +G0 filters?

For a long time I've really been into using several exposures at
different grades when making a print.

Sometimes, though, I'll have a print at, say, grade 2 where I want to
dodge highlights only and not the shadows e.g. the whites of eyes - if
the print consisted of an exposure at Grade 0 and another at Grade 5 -
this would be easy - I'd do the dodging during the Grade 0 exposure -
thus preserving the depth of the shadows.

What I'm asking is - is there any chart or formula where I can break
down an exposure of , say, Grade two into corresponding exposures at
Grade 0 and Grade 5? Would this involve an overall time increase in
overall exposure? Any thoughts?

I use Ilford Multigrade filters.