Writing an A-B Rallye
Length
50 RIs are a reasonable (rough) length for an A-B rallye.
Looping
There are four main types of RI in an A-B rallye:
- Same Location
- Both parts refer to the same action(s), performed at the same location(s), and the rallyist must determine whether each part is valid.
- Same Route
- Both parts occur along the same route, but not at the same location, and the rallyist must determine whether the first part is valid.
- Supp Style
- One part occurs beyond a turn for a gimmick (typically using Observe or CS), and the other part acts like a Supp to get rallyists back on route (e.g., "U at Smith, R 1st Opp").
- Looping
- The parts occur along different routes, with the two routes eventually rejoining.
Simple gimmicks based on instructions that are invalid per the GIs (e.g., misspelled street names or words that "do not exist on signs") typically use either the Same Location or Same Route type of RI.
More complex gimmicks (especially those that have rallyists turn on specific streets) cannot use the Same Location type of RI. When they use the Same Route type of RI, they tend to be more obvious because one of the parts will refer to the same turn as the higher-precedence gimmick. Rallyists need to realize that they should do the turn for the higher-precedence gimmick, rather than for the RI.
Using a Supp Style type of RI makes the gimmick less obvious, because those who do not get the gimmick will not encounter the landmark for the part that acts like a Supp. However, it is still relatively easy for experienced rallyists with maps to figure out where they would need to turn to do the part that acts like a Supp. From there, they can easily reverse engineer the gimmick. Thus, the Supp Style type of RI is very similar to the Same Route type of RI in practice.
Using a Looping type of RI makes the gimmick even less obvious. Rallyists who catch the gimmick will follow a different route than those who don't. Neither RI part will refer to the turn for the gimmick, and often neither group of rallyists (those who get the gimmick and those who don't) will encounter the landmarks used in the RI part for the other group.
Looping type RIs usually makes the rallye flow better too, because there is no need for a U-turn.