411..That wasn't in JED, was it?
Anyways...I've had reversers locked on 737, L-1011 and 777. Generally, there were no restrictions, other than what was in a company FOM that stated that an aircraft with a locked reverser could fly, but no reverse selected on a wet runway. Remember that all certification is done without reverser performance, so having a reverser is just a bonus.
Airmanship dictates that...don't use just one on a slippery runway, or ....one can get a full 360 degree look at the airport enviornment.