A Mistaken Shehechiyanu

A person sat in the succah on shabbos chol hamoed and made a שהחיינו by mistake after kiddush before he drank the wine. Is this considered a הפסק?

Someone is davening shmone esrei and realizes that he forgot משיב הרוח. He starts again from the beginning but then realizes that he said משיב הרוח after all. Is his second start considered a הפסק and he should continue from where he is or should he start from where he already said [past where he is presently holding] in the first shmone esrei?

According to the the Shaarei Tshuva [סי' קיד] the answer to our second question would be that he should continue from where he said the FIRST time. Since he thought that he was obligated to repeat shmone esrei, it is not considered a הפסק and he may skip to where he was the first time.  

Now we return to our first question. In the same vein we can say that since he was under the assumption that he was obligated in שהחיינו it is not a הפסק.

By the force of the same logic we can learn another halacha: After המוציא one is allowed to say "pass the salt". Even if there is no salt on the table it would still not be a הפסק because he wasn't מסיח דעת and assumed [albeit wrongly] that there is salt on the table.

Another question: Someone made havdala and then right before he drank the wine he remembered that he had already heard havdala, may he go ahead and drink the wine? Perhaps the bracha of המבדיל בין קודש לחול is a הפסק between the בורא פרי הגפן and the drinking. Based on our logic it is not.

עי' בקובץ קול התורה מג עמוד קנד, ויש להאריך בזה מאד ואין כאן מקומו ומה שהלב חושק הפנאי עושק.