But that public perception is clearly one of the reasons the normally faceless bureaucrat has emerged from the backroom to explain more about the process.
"I appreciate the opportunity because there has been a lot of press and a lot of it is not always accurately portraying the dynamics in the room or the common goals that the countries have around the table."
The aim this week for the 500 officials from 11 countries at the talks had been to integrate newcomers Canada and Mexico in the talks without slowing the pace, to bring some of the more technical issues to closure and to make some progress on the tougher ones such as market access.
They will continue next week.
"It isn't the kind of thing where people come into the room and they are heatedly arguing. It is a very serious, very professional atmosphere in the room.
"Countries are very honest and are interested in understanding what the concerns are of the other parties so they that can overcome whatever the differences are."
The intellectual property specialists have been working on trademarks and geographical indications issues (which cheeses can be called cheddar or feta, for example) and there was quite a bit of alignment between New Zealand and the US.
Other IP issues were more difficult, she acknowledged, but the differences had been "overblown".
"What I think has been misrepresented is [the notion] that the negotiation will come to a point where it will break down and will simply be unable to come to some sort of compromise that is acceptable to everybody and I don't think there is any evidence that we're approaching that ... this is a negotiation and the countries will come to an understanding."
On the issue of removing agricultural tariffs, she would not utter the words that that would have to be part of the deal, but reiterated the fact that every leader had signed up in writing to a commitment to a "comprehensive" agreement.
"What I want to emphasise is there is no question that these are very difficult, very sensitive issues," she said. "Countries are going to have to grapple with things that we have not in previous agreements either not taken up or necessarily concluded. Exactly how we get there, we can't tell right now. What we can say is there is a high level level of commitment to do that.
"We are looking to do a state of the art agreement and that is a difficult, challenging exercise. That doesn't mean that all 11 countries are not committed to doing that."
There would be a single schedule, she said, but different countries would have different ways of getting to the same point.
She suggested that would also be the principle in any investor state dispute settlement (ISDS) chapter - a private arbitration system that Australia opposes.
Asked if she thought it would be possible to have two options, no ISDS for countries that have high trust in each other's justice systems, such as Australia and New Zealand, and an ISDS for others, she said: "I think it would be very difficult to do that because once you set the precedent of having two standards on certain types of commitments you open the door to standards across the agreement on other issues that might be very important to have a single standard."
In certain cases where a developing country is new to an issue they are allowed time to phase in a particular commitment.
Weisel is currently an assistant United States trade representative with responsibility for Southeast Asia and the Pacific. The TPP negotiation has an informal deadline to be finished by October 2013. It is the only negotiation the Obama Administration is doing at present but it is being done without the security of the Trade Promotion Authority (TPA) of Congress.
TPA means that a concluded trade deal can't be altered by Congress; it is either accepted or rejected. Not having TPA leaves it more vulnerable.
But Weisel said she was conducting the talks in the same way she would have done with TPA.
"We have been consulting very intensively, very closely with our Congress at every stage of the negotiation. They have provided input to every proposal we have tabled in this negotiation and are consulted before and after every round intensively."
All 500 members of Congress had always had access to the text.
"Whenever they choose to ask to see a text, they are provided that text and that has always been our policy."
The next round of talks are thought to be in Singapore.