I think the FIA's point (God, I hate having to defend those *******) was that Hamilton and McLaren's testimony initially lead to Trulli getting penalised. When it turned out that they were less than truthful, and by being less than truthful had caused someone to be penalised when they shouldn't have been, they threw the book at them.
They could clear this up by giving the transcripts.
As they haven't released them, you do wonder what exactly was said. if it could have been a miss understanding or a total lie.
I don't have a problem with the punishment if they did lie, but why oh why do Stewerds not listen to the communications on the race day. I mean even listening to the entire lap would take 1min30 and it's not as if it's hard to get your hands on. that is what makes this a disgrace.