THE GROUND RULES seem to have changed again for the folks over in financial aid. Last year, their overwhelming worry concerned Harvard's image as a rich man's school--the danger that widespread anxiety over aid would discourage poor students from applying, undermining the College's cherished diversity. The challenge then was simply getting out the word that Harvard was sticking to its guarantees of full need-based aid. The admissions office met the challenge with new publications and stepped-up recruiting, but last spring's statistics showed some ground had been lost.

But admissions officers returning from recruiting trips now talk about another problem entirely. More than in recent years, says one, "We've had to restrain the alumni" from promising too much. Prospective applicants, it seems, are hearing too positive a message and applying on the assumption that Harvard will take care of everything--an assumption which despite all Harvard's protestations of "full aid to need" is not exactly the case.

Applicants who are most likely to get a rude shock are those whose parents are reluctant or unable to contribute heavily to their education. Harvard calculates "need" first on the basis of a family contribution, and complaints that this is unreasonably high comprise more than half of all aid appeals for reconsideration. Aid Director Seamus P. Malin '62 says.

Malin contends that inflated expectations of aid from Harvard spring mostly from small breakdowns in discourse: "Harvard will give you as much aid as it feels you need to attend does not equal 'Harvard will take care of you even if your parents won't.'" He notes too that it would be ridiculous to claim that nobody ever leaves Harvard for "financial reasons," regardless of aid policies.

"If a student comes to us and says his parents can't pay what we've figured out they can pay and his roommate's parents are paying that sum, then there's no way we can necessarily give him that money and not his roommate," Malin says. "And sure, those are 'financial reasons to leave."

Such differences in terminology may seem minor, but they can carry a disastrous effect, as became clear last spring. Though the number of Black students accepted had been comparable to past years, the number who actually came here dipped dramatically; virtually all observers agreed that large numbers of needy students had gone elsewhere because Harvard's aid awards were too stringent. A survey of students who turned Harvard down confirmed the impressions: 45 percent of all students and 62 percent of Black students said financial reasons figured in their decision; 21 percent of all students and 41 percent of Blacks called it the primary factor. And besides the immediate "loss of desirable and "diverse" students, such incidents are likely to have farther reaching implications, if, in addition to its other image problems, Harvard gets a reputation for big promises and subsequent disappointments.

David L. Evans, a senior admissions officer, has gone so far as to propose tinkering with the need formula--for instance, working some allowance for minority middle-class students into the formula to account for "hidden costs" minority families face if they are new to that income group. Pulling bricks out of the intricate structure of need-calculation is obviously a perilous business. But that should be no reason not to consider that or even more radical solutions to a problem which--as it is increasingly obvious--goes far beyond matters of publicity and image-building.

Whether or not Harvard says it guarantees full aid, events are beginning to drive home the fact that the actual dollar figures may still fall short. Obviously, no aid office anywhere can undertake to provide every needy students with as much money as he could possibly want in any contingency. But as last year's statistics and this year's fears show, neither can it convince students that their aid package is sufficient if large groups of students and their families find it isn't. All the needy and/or minority students in the world could apply and be accepted on the basis of Harvard's generous image. But scanner or later, reality catches up.