True and the crew did a great job, I'm sure the AAIB will be looking into why one of the links in the chain (crew pre-flight check) didn't spot this known problem.
I'm sure any footage that is available from the stand cameras at Heathrow will show whether this check was sufficient or needs further amendment.
I'm sure any conscientious F/O doing the pre-flight would bend down and glance at the cowls but it's clear that this isn't always enough to spot a problem.
I hope that this re-focuses attention on the problems with this cowl rather than a quick hatchet job on the individuals involved and forget about it.