"No Tie File esp for bioinformatics"

-- As it stands, this is appalling and irresponsible advice and I urge the OP to disregard it.

• It immediately struck me as FUD and flame-bait trolling.
• It's a very lazy response. It lacks any reasoning. You couldn't even be bothered to write Tie::File correctly.
• The OP did not mention "bioinformatics" nor, indeed, did anyone else (at the time of writing).
• Tie::File is a core module: there would be no problems with having to install this from CPAN.
• The "Tie::File - DESCRIPTION" has: "The file is not loaded into memory, so this will work even for gigantic files.".
• There is a potential memory issue but that can be easily mitigated: see "Tie::File - memory".
• The OP is only reading the file. There is no issue involving the rewriting of records from the point of modification.

Sorry, but I disagree with both your and the AM's posts, as the issue is much more nuanced than "never use Tie::File" vs. "appalling and irresponsible advice". I used to recommend Tie::File, until I did some testing to see for myself the massive performance impact the module can have even when simply reading a file (in that test 23x slowdown). Bioinformatics often deals with very large datasets, so any slowdown can be significant, though the OP didn't say how large the files being processed are.