Federation Commander

Are boarding parties rooted to their ship, or can they "loaned out" to another friendly ship? I don't mean to help defend the other ship, but rather to have one ship in the fleet act as the "labor pool."

Nothing stops you from doing that during a scenario.

Nothing allows you to do that before the scenario starts.

A fleet with a "commando" variant is very resistant to capture attempts, for the very reason that it can transport "loaned" boarding parties to its fleet-mates.

The flip side to that is that a fleet with one is also much more able to capture enemy ships.

My thought was a ship on point that is likely to have the snot blown out of him could leave his boarding parties behind, where they might do some good later.

Perhaps, but that means the receiving ship would have to drop its frontal shields, which is never convenient.

Using the rules provided, as Steve states, the marine unit allocation at the start of a scenario is fixed. Each ship has its stated allocation, no more and no less. Once the scenario starts, the marines can be reallocated as desired, but must do so under the rules. That means the marines must be reallocated through transporters, shuttles, and/or docking.

The one thing that would be an exception is if there is a specific scenario rule that delineates a modification to the starting allocation. (Typically this will take the form of either extra marines because of some special mission, or fewer marines because they were lost immediately prior the scenario.)

This just in from Captain Obvious...

If the point ship dumps its boarding parties to other ships, it may very well have the snot beat out of it, but it is also far more likely to be captured outright instead of simply destroyed. And capturing a ship is worth twice the points that destroying a ship is worth.