What really bothers me, as citizen of an european country, why is it possible to have secret deals? If I don't know about such deals how can I call my representative to oppose them? Or encourage them to take the deal if it's a good one. AFAIK, TTIP was leaked and that's the only way european citizens knew about it. Why is it legal? Because all I see is corporations trying to make a sweet deal with governments, and th…
Therefore it follows that anyone who can negotiate from a position of secrecy or absolute power (dictatorship) is in a better position to achieve his goals during a negotiation.
You might laugh at this but I believe this is exactly how the EU commission thinks about this. Maybe they will try later again in a more dictatorial manner since secrecy has failed, who knows.
The other extreme would be that you negotiate from a position where you are constantly attacked by NGOs and your own people, which certainly doesn't help with creating trust that you can follow through on anything you sign. You can certainly place your signature on a document but it means nothing because you can't execute.
This was actually a problem during the Cold War crisis between JFK and the Soviet leaders. The Soviets were hard to convince that JFK could follow through because he was so heavily opposed by his senior military staff. They actually believed that there was a real possibility that JFK would be disposed by a military coup so they thought a war between the Soviet Union and the US was imminent and acted accordingly.