[Koha] Import Question

I have a question about batchImportMARCWithBiblionumbers.pl I found a reference to this in a 2010 email. The scenario described, a library needing to retain their current control numbers as biblionumbers to continue connecting to outside databases, is the same thing we need to do. Unfortunately, I didn't see an answer to the question. The description of the script, "small script to import an iso2709 file into Koha with existing biblionumbers in marc record" made me wonder if I was importing a marc file into a clean database, if I had our current control number in the 001, if this script would use this value as the biblionumber. I know there are a lot of "ifs", but am I on the right track? Thanks, Lezlie Questia