use the approximate method of setting Vre to about 26mVre.
If you have a high Re then it swamps the internal Re and you set 26mV on the external.
If you reduce Re, then a higher proportion of the total Vre appears across the internal, so you have to guess at the optimum external Vre.
By the time you get down to 0r1 external, you may have only 18 or 19mVre across that value. For 0r24 maybe aim for 22mVre.
