Reasonable increments in boost for WOT cam timing

After completing steady state tuning, if for example WG pressure was 10psi and maximum boost target could be up to ~25psi, with mapped targets in-between, what would be reasonable WOT targets to run and interpolate results between? Would three MAP targets be sufficient of say 10, 17.5 and 25psi?

Or should the runs be skewed to the higher boost areas where back pressure might be increasing and be more likely to affect optimum cam timing, say 10, 20 and 25psi?

i like the idea of 10 15 20 25 you will not likely see any difference in 15-25