Howdy.
The following comments are offered in a friendly tone of voice and with some
humor too.
Since you wanted to start a discussion, I assume your question or interest is sincere.
Mast Floats have been used on smaller catamarans (beach cats) and on
dinghy sailboats for years. They may be added to a
boat for beginner sailors who are unskilled or worried about capsize, and may be seen in some sailing schools where beginners are likely to capsize frequently when first
learning to sail dinghies.
You can buy some “ready made” products (see Crewsaver masthead float shown below) or you could
DIY (see
blue water jug below...added for humor).
The
concept for large cruising cats has been discussed here on CF in the past, and generally dismissed as impractical for a large cruising
catamaran.
Doubts are usually raised about the practicality of such a float, the windage it would create if permanently mounted high on a mast, and the size needed to overcome or counter-act the capsize inversion.
Most remarks I have seen say it is simply unneeded by most cruising catamarans because most never capsize. In other words, it is a product
concept in search of a market with little perception of need (by most catamaran owners).
Doubtlessly, someone will think there is a market for a new product, etc.
Good luck and I hope this helps.