The documentation here
https://docs.civicrm.org/sysadmin/en/latest/setup/civimail/#bounce-processing
says
VERP can be disabled via the option Track replies using VERP in Reply-To header at Administer > CiviMail > CiviMail Component Settings. This will reduce CiviCRM's ability to correctly match bounced messages.
That is oddly confusing. I want the VERP to be used in the Return-Path header (I think), not the Reply-To header, so should I check or uncheck the 'reply-to' box ? If I check the box, how would it 'reduce' the ability to match bounced messages ?