Without commenting on the TPP specifically, I will point out that this is the process that the Constitution sets out for international treaties: the executive branch negotiates them as they see fit, then the agreement is presented to the Congress for ratification.

If TPP makes it that far (no guarantee it will), the Congress will have plenty of opportunity to read and react to it--especially now that Fast Track has expired. Just look at how many times the negotiators had to go back to the table on the South Korea and Colombia free trade agreements to satisfy Congressional objections.

Technically, you're somewhat wrong about other countries. For instance, in France, even if ACTA had no impact on the legislation, it would still require ratification by a law. Because, the list of treaties that require ratification is so broad in France (Art. 53 of the Constitution), that almost only symbolic agreements are exempted of ratification by the parliament (or referendum). And that's the case in most of European countries.