User blog comment:Sentry 616/Weapon Gushing/@comment-27144409-20190926025347/@comment-27144409-20191020033915

No, it refers to the specific tactic of a single artillery piece kitting some poor grid coordinate with up 5 shells at once.

The bulk of artillery casualties occur within the first 60 seconds, so the more shells you can land  before they have time to get safer and provide a less dense colleciton of targets, the better.