I think post length should be altered to get the specific shot - either to change the lens height range and/or the rig's inertia. Choosing to configure your sled only one way is like playing 10 keys on the piano instead of all 88.
Just remember folks, it is not just the weight, but the weight distribution that influences the "feel." Spread your masses to add pan inertia and you'll likely much prefer it.
If you don't have any other choice, this could help you :
- Have an assistant Raising or lowering your docking stand to the correct height for the shot
- Put your Sled on the balancing stud
- Put a magic arm between your post and the stand
- Frame the shot, than tighten the magic arm
Not as sturdy as a tripod but can sometimes help.