Wtf? It's almost as if people here are principleless partisan hacks.
If Obama promises my insurance premiums are going down $2500 (and they go up) how is that different than a corporation promising their weight loss supplement will cause me to lose 5 pounds when the reality if their customers tend to gain 10 lbs in trials?
Great question. glad you asked. Since I happen to work for one of the largest nutritional supplement companies in the US I have a lot of insight on that topic. "Claims" made by any manufacturer of products that are regulated by the FDA (and despite the BS the NY AG claims - there ARE extensive regulations, just like for pharmaceuticals) are required, by law, to be supported by defensible research and testing. A company cannot say they will help you lose 10 lbs unless they have performed scientific studies that support the claim.
Likewise, if there is reson to make a political claim, then it can be made, even if it turns out to no have worked out as intended, and reasonably predicted.
It was reasonable for Obama to have said he intends to close Guantanamo, as one example. He attempted to do so. No one told him it was impossible (unlike Trump's wall claim). The reason Guantanamo was not closed was because the partisan opposition team against Obama (the GoP) refused to pass the associated bills needed to accomplish it. It was doable and reasonable, and desired... but opposed. Not a lie, not a promise broken, an unfortunate circumstance brought on by another branch of government.
What I propose to be "illegal" is not correcting "errors" made in speech. Not proposing that the error in speech itself would be illegal. Opposition is conveniently (to their position of "give me unlimited and unchecked power) ignoring that and creating a "thought police" strawman. It would be a "contempt of court" charge, as it would be within a legal venue that it is decided what needs to be corrected, based on objective facts alone.