Justice John Griffiths said "one could understand" and "have some sympathy" for Mr Tarrant with the way ASIC conducted its case against him.

Mr Tarrant is claiming the Administrative Appeals Tribunal (AAT) erred in granting leave to ASIC to amend its statement of facts and contentions almost 4½ days into the five-day hearing in October 2012.

He told the full bench of the Federal Court sitting in Sydney this week that ASIC strengthened its case and came back with fresh allegations against him.

"Whether or not there is some error of law here remains to be determined," Justice Griffiths said, "but one can have some sympathy, can't one, with a sense of grievance that he feels about this which is now understandable … It is a complete and utter mess by the look of it."

Justice Steven Rares said "given that Mr Tarrant was appealing against this suspension and the impact on his livelihood, and the extra significant cost that could not be compensated, there's a real prejudice here".

He said the resumption of the case played in a "very different ball park for him ... from what he thought was the case against him".

ASIC counsel Elizabeth Cheeseman, SC, pointed out that Mr Tarrant had "other courses of options available" at the time which he didn't take, including holding ASIC to its original case.

Mr Tarrant was banned for seven years from acting as a financial adviser after recommending 220 clients invest in Trio Capital's Astarra Strategic Fund.

He lost his appeal against the banning order in the AAT and is now asking the full bench of the Federal Court to set aside the ruling, claiming there were 17 errors of law.

Mr Tarrant, representing himself, said the matters put against him by ASIC were "not of a serious level that would warrant any consideration of a lengthy ban".

"I was not involved in misappropriation of client funds, falsification or destruction of records, failing to keep financial records, carrying on a financial services business without holding an AFS licence, persistent contraventions, or insider trading or market manipulation," he said.

"The tribunal finds no evidence of dishonesty," he said.

"I was not responsible for the fraud or the losses to clients in respect of ASF. I had no previous history of contraventions ... I fully co-operated with ASIC throughout its investigation. I have assisted clients to take steps to recover funds by pursuing compensation from the Commonwealth upon the finding of the PJC [Parliamentary Joint Committee] inquiry that ASF was a fraud."

Mr Tarrant also challenged the tribunal's decision to refuse his requests for an adjournment when the hearing reconvened in June last year at "crucial times during the hearing".

"A request for an adjournment due to medical reasons was denied by the tribunal. I was not provided with the opportunity to present my case, cross-examine ASIC witnesses including their expert witness ... and proceedings continued without me."

The court has reserved its decision.