Although it’s not easy to capsize, I found my World to go from capsize to full inversion very quickly! My uneducated guess is that buoyancy in the sides contributes to this much more than buoyancy in the floor. Another thing from my small experience (1 involuntary inversion + 1 done on purpose for practice): if you go for a dive (for example to get the centerboard down/up, or to check the sheet cleats) don’t expect to be able to catch a breath under the inverted World.
On my second inversion event (it was performed by Ralph Roberts and me = 2 x cca 75kg), we had a *very* difficult time getting the boat upright again. We didn’t understand why was it so. Next time i do this, I plan to attempt furling the foresail underwater before starting to spend energy on righting. If it’s possible, I think it might make righting much easier, and reduce chances of another capsize when rig comes out of the water and gets hit by a gust.
As I had the transom flaps permanently closed, once the boat righted from inversion, it felt very unstable with all that water running across the floor from side to side. Of course, just like The Book says, once it gets sailing again, the bailers drain the cockpit relatively quickly (it can never be too quickly!). So in order to improve cockpit draining time, I intend to modify my transom flaps so that they can be brought back into function by simply releasing a shock-cord line from in front of the storage box.
Just like you, I would like to add myself to the group of citizens that doesn’t want to believe in flying balloons on top of the mast in heavy air, nor rely on mechanisms which can’t be checked or tested (maybe Simon or Dave M. could deny this – I haven’t owned a Secumar myself). We need some more testing to see if there is a reliable and easy procedure for righting the World without these aids.
Also, I would like to add that in-spite of this issue, I wouldn’t change to another type of boat except maybe to a woody for it’s classic appeal. In my humble opinion, it is a sad thing and a step back for aspiring dinghy cruisers that the World version with it’s beautiful curved lines and it’s intelligent features was killed by the new license owner/designer.