Lord Rogers has kept a low profile since he was sacked from the Welsh Assembly project last week.
But there have been two notable exceptions: a quick question-and-answer session on Radio 4's Today programme, and a longer recorded interview for BBC Wales' Dragon's Eye programme. In both, he makes disturbing allegations about the management of the project.
Lord Rogers reserved his most forthright comments for television, suggesting there was someone behind 'a complete smokescreen' attempting to kill off the project. 'This is classic stuff. Somebody is trying to destroy the building, ' he told the programme.
'Somebody is misleading the Welsh Assembly.'
Lord Rogers is disturbed on two counts: firstly that the apparent cost of the project has risen so sharply within a short space of time; and secondly that Assembly members are even beginning to believe that the design will not work.
But the only way costs could rise so steeply was if the decision had been taken to pave the Assembly in gold, Rogers insisted. And politicians had no right to question the integrity of the engineering, he said, adding that Arup would not allow the practice to build a roof which failed to work.
'Somebody is making these things up, ' he said, adding that Assembly managers were guilty of 'horrific incompetence'.
Lord Rogers also said the chances of another team picking up the design and delivering it at a lower cost was 'just about zero'.