Answer ... It is very common to discuss transactions in advance with the tax authorities and to request advance tax rulings.
Especially in contentious cases, the authorities will usually seek to understand the economic reality and will be less inclined to recognise a mere legal or formal framework. It is therefore paramount that a given structure have economic reality and substance.
Given the federal organisation of Switzerland, the administrative practice regarding a specific legal question may vary considerably, depending on which canton will ultimately be responsible.