> The question was not "is this a good idea?" nor "do folks do this?" 
> but rather, is there any proof that old comb has a negative effect 
> on colony growth. I have not yet seen that question answered definitively.

Negative implications for colony growth are mentioned in the literature,
such as: 

A Biometrical Study of the Influence of Size of Brood Cell Upon the Size and
Variability of the Honeybee (Apis mellifera L.) by Roy A. Grout, 1931

http://lib.dr.iastate.edu/cgi/viewcontent.cgi?article=1232&context=researchb
ulletin
https://tinyurl.com/y8zdkbz5

"The reduction of the size of the brood cell by the accumulation of the
cast-off pupa skins, cocoons, excrement and varnishing resulting from each
generation has been discussed by Quinby (30), Dadant (10) and others. All
maintained that the lengthening of the side walls of the brood cell
compensated for the slight thickening of the side walls and that the volume
of the cell, if reduced, did not materially affect the size of the emerging
bee.  Tuenin (36), upon weighing bees that had emerged in. succeeding
generations up to 48 generations and measuring the brood cells, showed a
reduction in the weight of the bee and a corresponding reduction in the
diameter of the cells. Michailov (26) continued this experiment by measuring
five physical characters of the endo-skeleton and showed that after 16 to 18
generations a reduction of 5.89 percent occurred in the diameter of the cell
with a significant reduction in the size of the bee. A reduction of 3
percent in the diameter of the cell showed no significant decrease in the
size of the bee. Rupp (33) calculated, from the data obtained by Michailov,
that a comb is too old for brood rearing when it is 3 years old."

I think all can agree that most all beekeepers use brood comb older than 3
years without trouble, so Rupp's findings above seems to be one of the
"beekeeper Just So Stories" so prevalent in the historical literature.  

But the size of the bees isn't the point at all - it is the wasted time and
effort of house bees fighting (unsuccessfully) to simply clean a cell that
is the obvious and serious drawback here.  A few layers of cocoon are not a
big deal, but at some point, the bees MUST rip out at least some of those
cocoon layers.  So, bees that might be feeding brood, or processing honey
are doing janitorial work, while the bees of an age only suited to making
new wax are also wasting their time because the old  combs are still sitting
there, and there are no recycled frames to draw out.  Yet the wax-making
bees do not cease making wax, they have nothing better to do, they are
"obeying" hormonal development.  So the efforts of two sets of bees are
wasted.  

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