[Rigelian]

Yes you can. Make sure both the fleet and the troop transports have Capture Planet strategies. They can break formation as much as you like.

I will have to try this again in a solo game.. I thought that this would result in the ships wiping the planet before the transport could get there. I always follow that scheme in any event (fleet AND troopship set to 'capture planet'), but I thought I had to keep the fleet in formation.

If you are using the correct strategies, ships stop firing on planets as soon as the weapon platforms are destroyed. With low population, it is possible for the Last shot to do enough extra damage to glass the planet as well as destroy the Last WP.

Yeah, the low-pop scenario is what concerns me. The problem is, each ship will unload all or none of its ordnance on that Last turn - and if we are talking about the multiple napalm-bomb ships I use for planetary assault, they often wipe out the 100M+ pop in the final volley. What I was looking for was for the ship to fire 'em one at a time, so that there is a chance of preserving the population.