I like to practice by using drones and use it to become aware of the possibility of any chord. Some of my friends and colleagues in the community band where I play use to practice the harmony lessons that our band leader gives us. These lessons are difficult to bring into practice if you attempt to do that within a musical piece while they become a lot more clear on a one chord drone.
Practicing on drones helps you building a vocabulary on all chords and makes it possible for you to elaborate in keys where you not usually would practice.
I disagree on the reeds treatment.
Reeds are not dying because they are dissolved by bacteria, fungi or yeasts and Listerine is not capable in itself of keeping reeds from being mechanically stressed beyond the capability of the fibres or to do anything to these fibres to be rejuvenated.
True that an extremely dry reed will die before of a well soaked reed but simply because reeds become more brittle when dry that they are when wet.
Of course most well played and rotated reeds are, under normal conditions, not drying completely even when they appear to be dry in a normal climate, and by playing, because of the moisture we have in our mouth them they quickly rehydrate.
A reed that is kept in a very dry environment, and air conditioning contributes heavily to dry conditions, will tend to be very dry to the point that it might lose its natural elasticity.
So, several players take to keep reeds continuously moist so that they can take a reed and use it quickly without rehydrating it first. Moisture and heat are a bad combination conducive to the formation of fungi and yeasts moulds.
So it becomes necessary to put something into the water to keep it as close to deadly for these things as possible without poisoning the person who is using the reed.
Various spirits (vodka being one of the favourites) alone or in combination with other liquids, also Listerine, are used for this purpose.
On the other hand, immersion in water for only few minutes prior to playing, under these conditions achieves pretty much the same result and in hot water it is even better (try a cup of tea 🙂 ).
The Jar full of reeds routine is, in my opinion, nothing else than one of the so many apotropaic rituals that many performing artists follow.