Thanks for pointing that out Lew, I see how the language in the
abstract is unclear. However, in the full text they make it more
obvious that they are talking about successive steeps with the same
leaf/bag. The full article is available on ScienceDirect (http://
dx.doi.org/10.1016/0963-9969(96)00038-5) if you have a subscription or
university access.

-Brent