drafting and pace setting in tandems and races
In solo marathon swimming, it is universally accepted that drafting and pace-setting are considered a form of assistance hence not allowed.
In marathon swimming races, the act of drafting other swimmers is integral to the sport at the top Olympic level (i.e. pack swimming), however, drafting off the escort draft is not allowed (Fina OW manual 2017). This is similar to drafting in cycling races that even in draft-legal races drafting off the leading motorcycle is not allowed. However there are some races which explicitly forbid this practice. For example, in USMS rules, drafting is prohibited in races where individual motorized support boat is used (303.9.5), and left to organiser's discretion in races where individual non-motorized support boat is used (303.9.6). In Rottnest Channel, the race rules forbid drafting and pace setting as well.
So what's the mainstream opinion now? I used to think that drafting and pace-setting are integral part to races that I devise strategy who I should draft or swim along-side in races in order to gain maximum benefit. We also do drafting practice in swim squads.
Outside races, in a "tandem swim" (i.e. at least two people swimming together sharing a support boat and crew), by definition pace setting happens because they are required to swim alongside to the other. In this case, is the act of drafting commonly accepted as well? (i.e. two swimmers position deliberately place themselves one after the other, sometimes rotating in order to save energy, benefiting both along the whole course)
A side question - does the MSF documented swim process ratify tandem swims in addition to solo and relay?