Unfortunately, "moderate" is used in a relative sense. This distinction can be lost on the public e.g., the public might view President Rouhani as a partner with whom the U.S. can easily do business. That he might be moderate relative to ex-President Ahmadinejad does not mean that he desires a constructive relationship with the U.S. Putting aside his rhetoric, one sees only small movement on the nuclear front (far short of what is actually needed to alleviate the concerns of the international community and Iran's neighbors), continuing involvement in assisting Iranian proxies such as Hezbollah, no changes in Iran's hardline rejection of Israel's legitimacy, etc. As time passes, and big changes fail to materialize, I suspect that the American public will become disillusioned. Yet, the disillusionment will largely be the result of oversized expectations based largely on hopeful assumptions that had little grounding in fact to begin with.
I see no reason not to reach out to him to "test" him. There may be some areas where improvement in relations could be possible. But my expectations are low overall. First, he is a product of a state that retains a revolutionary ideology that runs counter to American interests and allies. Second, Iran is seeking regional hegemony. Third, Ayatollah Khamenei wields the real power and that would limit any big changes in direction. Iran should be judged by its actions, not its softer rhetoric. To date, its actions remain largely unchanged and the progress to date in the nuclear talks is mostly a matter of process. There is no concrete agreement to limit or end Iran's enrichment activities, much less for it to eliminate its enriched nuclear material. No breakthroughs on that front appear imminent.
