Bucky's Tuition Promise (BTP) at the University of Wisconsin--Madison offers generous financial aid to low-income, in-state students. Unlike many similar programs at other public universities, financial eligibility for BTP depends solely on a family's Adjusted Gross Income (AGI), rather than on the Expected Family Contribution (EFC) from the Free Application for Federal Student Aid (FAFSA) or some function of the poverty line. This program design aims to make eligibility simpler and more transparent for students and their families and thereby to encourage application and matriculation. We investigate the implications of the program design for who does and does not receive additional institutional aid, with a particular focus on the marginal group of BTP-eligible students who lack Federal Pell Grant eligibility. With this analysis, we aim to motivate a broader discussion of different notions of equity in financial aid administration and the tough tradeoffs implicit in simplifying eligibility criteria.