A lot of what you said is just wrong. The largest increase in inertia for a given mass is obtained when the mass is distributed the farthest from the COM not equidistant. If the moment of inertia is the RW and your racket is HL adding mass to 12 o'clock increases the RW the most until the racket becomes HH then adding mass at the butt increases RW the most.
t.
you are violently agreeing with me
but I can see I was not precise - equidistant and farthest away
so if the racquet were constructed of two equal masses the greatest moment of inertia would be about the point mid way between them with two equal masses - center of mass in equal distant between the two equal masses
yes if you make the racquet longer, it will increase in moment of inertia,
that is what you are saying in your quote and I agree,
that means for the highest recoil weight (moment of inertia about the center of mass) for a given mass, you want the balance point (center of mass) to be in the middle
lets take a 27" racquet that I want to have a mass of 300grams
27" = 68.58 cm
Lets assume i can make it out of two masses in which the total distance between the two can't be larger tahn 68.58 cm
i could make the masses equal
the center of mass would be 34.29cm from each mass of 150 grams
the moment of inertia about the center of mass would be 352741 gram cm^2
34.29^2 * 150 + 34.29^2 * 150
lets put the center of mass 6.868 cm from one end,
the mass closest to the center of mass would be 270 grams and the other mass would be 30 grams and 61.722cm away
moment of inertia 126987.8 gram cm^2
270 * 6.858^2 + 30 * 61.722^2