Self-collision of European patent filings: an accident waiting to happen?

It is a common legal premise around the world, including in the important territories of the USA and Japan, for an applicant’s own earlier filed but later published patent filings (an earlier filed co-pending application) to be unavailable for the assessment of patentability of subject matter that is claimed in a later patent filing for the same applicant and which has a filing date before publication of the earlier filing (a later filed co-pending application).