When asked on the sidelines of the conference in his talk with reporters if the compliance date would be extended, Hauser replied: "Never say never," but firms and advisers and others need to comply under the current timeline.

"If we had all the answers right now, we couldn't get it done by January 2018," Anthony Palermo, vice president and senior operations relationship manager at American Funds, said.

The fiduciary rule itself becomes effective April 10, 2017, Hauser said, with the full conditions of the exemptions in effect in January 2018.

Hauser said that he expects the DOL to issue Q&A guidance on a rolling basis, as it's the most efficient means. However, he noted that the DOL would like to hear from a fair number of people about their concerns before issuing such guidance.

"I'd encourage you to reach out. You can call or write, it doesn't have to be formal," he said.

As to enforcing the rule, Hauser said that in the "near term, which I would view extending to January 2018, the goal is to assist and facilitate compliance" with the rule, "not finding litigation targets."

But Paul Schott Stevens, the ICI's president and CEO, noted during remarks at the event that ICI members are frustrated with the course that's ahead in complying with the DOL's rule, noting that there's real reservations and puzzlement about the way forward under the rule and that people are now investing in new efforts to conform.

He noted that the ICI still believes that the fundamental, far-reaching questions raised by defining a fiduciary standard should be addressed by Congress through legislation that could apply to all financial advisers for all accounts – not through a litigation-oriented contractual regime, imposed by regulation and applied solely to retirement savings.

With its final fiduciary rule, Stevens continued, the DOL has launched, in effect, a grand experiment to see whether investment providers can continue to meet retirement savers' needs under the strictures of a novel contractual regime never anticipated by ERISA – and under constant threat of strike-suit lawyers and class-action litigation.

Stevens said, "None of us – in candor, not even DOL — knows exactly how this experiment is going to play out."

Rep. Phil Roe (R-Tenn.) reiterated during luncheon remarks at the ICI event that the House's joint resolution to block the DOL's rule under the Congressional Review Act will be vetoed by President Barack Obama if it reaches his desk.

Roe co-sponsored the resolution, which passed the House on April 29, along with Reps. Ann Wagner (R-Mo.) and Charles Boustany (R-La.).

If Donald Trump wins the presidency, Roe said, "and we are able to legislate on DOL's rule, there's a great chance to overturn some of this [the rule]. But if Hillary Clinton wins the White House, you won't see change in DOL's rule."

Roe said that he's now working on a bill that would begin retirement savings at birth.

"If re-elected for another term, I'm going to be pushing for this," he said.