When Democrats and Republicans assembled at Harvard this weekend to discuss "the parties and the nominating process," neither party expected to emerge with any new or dramatic proposals.

Party leaders, therefore, were not disappointed yesterday at the meeting's conclusion, having at least gained the experience of discussing "common ground" at their first joint conference.

"We make a mistake if we look for consensus" Ronald H. Brown, deputy chairman of the Democratic National Committee (DNC), said Friday at the pitset pf the conference. "We've been talking among ourselves as Democrats. and we came to hear some other thinking."

Democrats are "talking" among themselves in an effort to reform--through the DNC's Commission on Presidential Nomination--a variety of their party rules that experts say contributed to the Democrats' defeat in 1980. "We can change things for 1984," Brown said, adding that "our process is already in motion, although it's always helpful to get other views and ideas."

By contrast, Republicans "don't desire to do anything" significant about reform, Roger A. Moore, general counsel to the Republican National Committee (RNC), said Saturday. Even if they wanted to reform, though, the Republicans are prevented from changing their nominating rules for 1984 because of party regulations that permit changes for the next election to be made only during conventions.

But Moore expressed concern that changes in state legislation, made by Democrats in the 35 state legislatures they control, could force Republicans to alter their rules before 1984 because Republicans incorporate state laws by inference. By coming to the conference, Moore and his fellow party members have had an opportunity to air such concerns to Democratic leaders.

The Republicans "don't want us to do anything too radical," Brown said.

As it turns out, nobody did anything too radical this weekend, as political scientists and politicians convened simply to share views about party strength and the process of nominating the president. Conference participants reached basic agreements on common concerns and goals, most of which were topics of discussion at round table sessions on Friday and Saturday.

With the exception of one provision, however, every proposal in yesterday's draft reports was called a matter of party jurisdiction, and not a question of legislation.

The only proposal that drew support for legislative action was a recommendation that states select convention delegates by "a process which restricts participation to members of that political party."

Other conference proposals and agreements were left to be implemented by future joint-party commissions, or to be considered when each party next meets to consider reforms. In the case of the Democrats, this means that they will be looking at the conference findings in January at their reform commission's next meeting.

"We didn't want transformation or unanimity," Jonathan Moore, director of the Institute of Politics and host of the conference, said yesterday, adding that this weekend's discussions provided the participants with a "greater sense of mind and a higher sense of ambition to operate from."

Both Roger Moore and Ronald Brown believed that the conference had some significance for their parties, if not an immediate effect. "It laid important groundwork for the possibility of doing things on broader issues in the future," Brown said.

As Moore viewed it, the conference was most successful in increasing cooperation between the two parties "on structural matters" which, he said, often hinder the nominations and election processes. Terming the meeting "quite remarkable," Moore added, "My only concern is that we didn't do it 15 or 20 years ago.