Hudson, re moving the thrust levers near reverse in flight; I hope that the system design has at least two other interlocks in it, i.e weight on ground or wheel spin up in addition to the thrust levers, thus several failures would be required before the ground spoilers could deploy.
Re the calls to be made with deployment (or not) of the airbrake / ground spoilers.
There could be several human factor problems here. First, if a 'deployed' call is always made it become routine and may be given in error when the system / crew has failed; NB BAe146 landing overrun at Aberdeen. Then there could be problems for crew who change aircraft types, they may revert to previous habits.
In general, calls should be negative; this gives greater impact for the failure case.
The issue of calls was reviewed in the NTSB investigation into the AA MD82 accident in Little Rock. One recommendation was made as below, but this may have introduced as many problems as it cures; increased workload, opportunity for error, etc:
For all 14 Code of Federal Regulations Part 121 and 135 operators, require a callout if the spoilers do not automatically or manually deploy during landing and a callout when the spoilers have deployed, and verify that these operators include these procedures in their flight manuals, checklists, and training programs. The procedures should clearly identify which pilot is responsible for making these callouts and which pilot is responsible for deploying the spoilers if they do not automatically or manually deploy.