Accuracy of traditional Legendre estimators of quadrupole ratios for the N to Delta transition

We evaluate the accuracy of traditional estimators often used to extract N to Delta quadrupole ratios from cross section angular distributions for pion electroproduction. We find that neither M1+ dominance nor sp truncation is sufficiently accurate for this purpose. Truncation errors are especially large for EMR, for which it is also essential to perform Rosenbluth separation. The accuracy of similar truncated Legendre analyses for E0+, S0+, and especially M1- is even worse.