[ODE] use fixed joints or not?

[Thomas Beer]

Asking myself why i didn't add the fixed joint to our script-binding 
some years ago I browsed through the ode docs and found two different 
comments on fixed joints:

first one:


      7.3.6. Fixed

"The fixed joint maintains a fixed relative position and orientation 
between two bodies, or between a body and the static environment. Using 
this joint is *almost never a good idea in practice*, except when 
debugging. If you need two bodies to be glued together it is better to 
represent that as a single body."

second one (in 8.1.):
"It can likely be shown that you will get a better performance to 
stability ratio by spreading out mass among several bodies connected by 
fixed joints rather than trying to implement it as one massive body, 
especially if that one massive body means you have to switch back to 
dWorldStep 
<http://www.ode.org/ode-latest-userguide.html#func_dWorldStep> to keep 
things stable."


Should I use fixed joints or not? Is it better to use a 
ball/hinge/whatever joint and constrain it's stops? Or should I bump it 
all into one single body?

Thomas