Thanks for the replies!
I think I realise where there may be some misunderstanding...
The biggest thing I've ever flown is a light twin and I assumed that jet aircraft did a 'power check' like you would in one of those, or a single engine piston - prior to departure at the holding point...
In essence; I thought that jet aircraft at some stage went to a 'higher' power setting beyond idle or whatever you set the engines at while holding on the ground (prior to departure); as some sort of 'power check' - to check certain systems - one thing being (my concern) that the thrust reverser's were locked, before attempting to take off.
Just trying to establish whether or not an unlocked thrust reverser would always be detected on the ground prior to take-off.
My question surrounds light/business jets, primarily.