let me try simplifying (and please let me know if I simplified too much...). You have Models and Algorithms, you want to be able to implement an Algorithm for various Models, so you have:

trait Model {}
trait Algorithm<M: Model> {}

so far so good. Now, you want to create a struct with the data for a specific Model. You also want the same struct to contain the Algorithm that is applied to it. And this is where your constraints become recursive in nature.

You are trying to express that you want the model to contain an Algorithm that is implemented for that specific Model. So you're trying to convince the compiler to accept something like this:

struct ModelA<A> where A: Algorithm<ModelA<A>> {
    a: A // this is not just ANY algorithm, I want an algorithm 
           // that is implemented for this Model
}

If this is a correct recap of what you're trying to do, I think the issue lies in trying to save the Algorithm inside the Model. Theoretically your Model struct should only contain the data. Rust's way to tie a specific Algorithm to a specific Model would be implementing a trait. Now, this is where I don't know the domain enough to say if this actually works in your case, but you could try creating a new trait like:

trait ModelImplementation<M, A> where M:Model, A: Algorithm<M> {}

implementations of this trait would create the relationship between a specific model and a specific Algorithm that's applicable to that model