1 TB of available space you already have is entirely practical.
with 1TB he will earn (with current price) 1.22$ per month. Do you think that is in any way profitable or just worth losing 1TB of storage for ?
If you have the 1TB of free space already why would you NOT class it as profitable?
Note that I'm not specifying "1 TB on a single drive", nor am I saying ANYTHING about if it is worth buying drives specifically for BURST mining (which I think is a waste at this time as there are much more profitable things you can do with the money, even buying the Seagate 8GB Archive drives with their VERY favorable MB/$ ratio would give a VERY VERY long payback).
By your own figures, that would be $1 and change that would not happen otherwise.