repetition - Rules for repeating "to"

I often don't know whether I should repeat the "to". E.g.:

To enable the car to perform jumps between blocks or simply to go faster, accelerator blocks can be placed, which as the name indicates increase the car's speed.

vs.

To enable the car to perform jumps between blocks or simply go faster, accelerator blocks can be placed, which as the name indicates increase the car's speed.

Is there any general rule to decide between those two options?

Answer

The repeated to is needed to make clear that go faster is parallel with perform jumps. That is, the repeated to guides the reader to parse the sentence like this:

• To enable the car
  
  
  
  • or
    
    
    
    • to perform jumps between blocks
    
    
    • to go faster
    
    
    
    
  
  
  
  
  

rather than like this:

• To enable the car to
  
  
  
  • perform jumps or go faster
  
  
  
  

That is, the repeated to establishes that there are two things you might want to enable the car to do: perform jumps or go faster. Leaving it out leads the reader to regard "perform jumps or go faster" as a single thing that you could enable.

The fact that this is so subtle and confusing suggests that the sentence should be rewritten from scratch. The sentence is confusing for more reasons than just the weird situation with or. For example, what is the distinction between increasing the car's speed and going faster? Another problem is that the sentence tries to say too many things at once.

I can't tell for sure what the sentence is trying to say, but here's an attempt at a rewrite (after I googled and found the document that the sentence is from):

Passing through an accelerator block makes the car go faster. This is needed to make the car jump over gaps in the track.

This rewrite might be wrong, but at least it's clearer. Clearer still would be to say something like how fast a car has to be going in order to successfully jump a gap.

---

BTW, here are some more things that would make the paper a lot clearer.

• 
  

  State explicitly what problem you are solving. For example, "Will the car complete the track?" or "Can a car complete the track?" or "Will a given set of player decisions lead the car to complete the track?" (I'm only guessing.)

  
  


• 
  

  State the rules of the game. For example, "When a car comes to a fork in the road, the decision of which way to go is made randomly" or "All the player's decisions consist of choices of which way to go at each fork in the road." (I'm only guessing.) "A car fails to complete the track if [list of failure conditions]."

  
  


• 
  

  Since you're talking about NP-completeness, you need to state the polynomial's variable: number of forks in the road, number of blocks, or whatever it actually is. State explicitly what thing in the tracks corresponds to variables in 3-SAT. (Does a variable correspond to the choice made at a fork in the road?)

  
  


• 
  
  

  If variable gadgets, crossover gadgets, and clause gadgets are not well-known to your audience, briefly explain them or at least include a reference to a paper that explains them well.

  
  


• 
  

  Instead of "These 3 gadgets demonstrate…", write an actual proof: show the gadgets and demonstrate that all possible whatever-is-relevant-in-tracks correspond to these gadgets and that the gadgets can be connected in the proper way. For a model of how to write such a proof, look at a similar paper in the field, like this one. A reader should be able to verify each step of the proof.

  
  

Apologies if that document is just a draft in a very unfinished state. I see a lot of academic papers actually submitted to conferences that omit nearly everything needed to understand the point of the paper.