kingRB,
I've found some material on the 114 engine, and agree that, unlike other variants of the PT6 engine, the 114 does not have a torque limiter.
The only limiter is the "secondary governor" which limits prop RPM in the event of overspeed. It works by limiting fuel flow from the FCU, so this action would be bypassed in the event of EPL use.
This is the only protection that is not available with EPL use. What other protections does the engine have? None - there are no other protections. There is no torque limiter, and there is nothing to limit Ng or ITT.
So, what this all means is that you can use the power lever to exceed normal engine limits and get that extra power. No need to use the EPL.
Using the EPL bypasses all of these in the typical case of a P3 failure or any other reason the FCU may stop working correctly.
Wrong. The only place the engine gets fuel from is the FCU. That fuel is always "metered". The difference with EPL use is in how the metering is done. Your statement could be considered correct in a functional sense, but that functional sense tends to imply that the EPL is providing fuel by an alternative source that exists alongside the normal source - hence the idea by the OP that you can get extra fuel via the EPL, and this is wrong.
perhaps you are the one needing to brush up on what the power lever does
Ok, so we don't know what the power lever does! Sure, we know what happens when we move it - pushing it forward results in an increase in torque, ITT and Ng, but how does it make the engine do those things? The reason I ask is because if you knew, it would be very clear that there is one source of fuel to the engine, and that this fuel is always metered. You would also know where the EPL fits into the scheme.
Have another go.