IrreversibleMigration too strict? Using almost any method causes an offense even when the migration is reversible

[dentarg]

Silly example but

Sequel.migration do
  change do
    alter_table :cars do
      add_column 'foo' + 'bar', :text
    end
  end
end

$ bundle e rubocop --only Sequel/IrreversibleMigration migrations/003_test.rb
Inspecting 1 file
C

Offenses:

migrations/003_test.rb:6:24: C: Sequel/IrreversibleMigration: Avoid using "+" inside a "change" block. Use "up" & "down" blocks instead.
      add_column 'foo' + 'bar', :text
                       ^

1 file inspected, 1 offense detected

I assume the docs, that say this

The change block can usually correctly reverse the following methods: ...

means that there are migration methods in Sequel that isn't reversible, and it is those this cop wants to catch. Here's a recent example where one such method was made reversible jeremyevans/sequel#2060