I go back to one point. We are dealing with a Hunter 26 trailerable sailboat in this specific case and the booms on the smaller boats are not as stout as the bigger boats. As for the mainsail on the Hunter 26 and 260, look at the way the sail is made. There are good points to both sides but not sure if a foot loose sail on this specific boat is really necessary. Here we go again on the comments but each to his own and I have said enough.
It may not be "necessary", but there are advantages to a loose footed main.
as for the boom being lighter or heavier, and it makes absolutely no difference the brand or size of the boat, i have never seen the time when the foot of a slugged down sport mainsail (as opposed to a racing sail) was full and tight with wind.
They are cut to have some bag in the foot.
So with this knowledge, you should be able to realize that a boom vang and mid point sheeting are both the most hazardous arrangement to the integrity of the boom.
end boom sheeting will always be the strongest and safest method for the boom itself...
The thread may be about loose footed vs attached mainsails, but it seems like the forces on the boom is in question, so...
With mid point sheeting or a boom vang trying to pull the center of the boom out of column with the ends, while the sail full of wind is trying to pull the boat along by the tack and clew of the sail, it should be easy to see where the problems are... there is not enough "up" pull on the middle of the sail, no matter how its connected, to counteract all of the point loading being inflicted by the vang or the mid point sheeting... if there was, it would pull the sail out of shape when you want it most.
A loose footed or slug footed sail makes no difference to the boom...
But a vang and midpoint sheeting does, and the lighter the boom, the bigger difference it makes, yet people dont seem the take this onto consideration (or care) when they modify things...
The only real advantage to a slug/boltrope footed main, is that they can be used to collect rain water when cruising off into the wild blue... and they can be easier to flake down without falling off the boom.