Target leavening volume

[JimmyG]

Tom,
   I had a question about maximum leavening volume before baking. Myself and many other bakers by convention aim, at most, to double our initial dough volume before opening up our skins. Looking through some of the cereal, food chemistry and microbiology journals, however, I have noticed that almost all of the researchers who are conducting experiments on dough leavening are shooting for 2.5x their initial dough volume. My question is: is there a specific reason they are aiming for 2.5x their initial dough volume, should this be something pizza makers should try to aim for, or is doubling good enough?
Thanks,
Jim

For those who are curious, here is an open access example of one such article. http://onlinelibrary.wiley.com/doi/10.1046/j.1365-2672.1998.00570.x/full

[The Dough Doctor]

Jim;
It is all just a matter of preference. I've seen numbers as low as 1.5 fold increase and as high as 2.5 fold as cited in the article. I normally shoot for a 2 fold increase in size. Remember, you will not be fermenting the dough in a graduated glass beaker, as they were in the article, but rather you will be "eyeballing" the dough to ascertain the magnitude of size increase. Why do I use a 2 fold increase? Because it is easier to say "Yup, that looks to be about twice as large as it was when I started".
Tom Lehmann/The Dough Doctor

[JimmyG]

Thanks Tom,
    I have never seen in the methods section why a particular volume was achieved or any citations behind measurements.  So I wasn't sure whether this was a common knowledge practice within the food sciences with a particular purpose or an arbitrary decision point decided set by the researcher. Thanks for your clarity.
Jim
~BTW, I am a little embarrassed to admit this but I'm a graduate student (in human nutrition) and do actually have a few graduated beakers I keep around the kitchen for measuring things or that I use for using as drinking vessels for other graduate students.