[ODE] Russ' plans for ODE?

[GARY VANSICKLE]

[snip]
> I disagree that it would need to interoperate with the internals, the
> only way it effects the simulation would be through an added force, so
> the buoyancy code would only need to call dBodyAddForce(), not any
> internals.
> 

Integration.  Calling dBodyAddForce() every step and doing buoyancy
externally means you're forever limited to forward Euler integration.  Not
cool.