[ODE] Leftover step time step instability

[Matthews, Steve USA]

> > 
> > Can anyone tell me why trying to step by this leftover time 
> would create instability? 
> 
> If the timestep is very small, you may end up with some 
> division by zeros,
> or something close.
> 

Yeah, I figure you're probably right about the division by near zero.  I just can't figure out why it isn't consistent, but thanks.

> 
> time_to_make_up += amount of wall clock time that has passed.
> 

That's a brick hitting me in the face; I guess I should have thought of just keeping the 
leftover time for the next step.

Thanks much for the help!!
   Bootshine