That power difference is pretty much common to all types that use those engines.
In fact I can't think of a single aircraft I flown in the last 6 years that hasn't had a bit of a split in either torque acceleration response or lever split.
I think the last time I flew one that didn't was when two aircraft got imported from Japan in 2004. Don't worry it only lasted for a week and then they were back to normal. Its one of the reasons why they gave us a rudder and we know how to use it.
http://www.aaib.gov.uk/cms_resources...pdf_033317.pdf
Again a beta in the air accident.
I was always told that with these props that the big spring that drives the props to fine isn't strong enough to drive the props fine again against aerodynamic forces once in beta in the air so I am quite surprised they got any power back.
The dirty secret is that you can get away with busting limits
This is the problem. And one which is extremely hard to battle against once it becomes normal. And don't think that it just apply's to so called third world airlines and pilots. It is alive and kicking in the UK as well away from the big boys with there QDR's. Most have beaten the approach ban and landed in sub 550m off a CAT1 I think my lowest has been 250m RVR after being 600m RVR at 4 miles and 400m at 2 miles, all I can say is the CAT II lighting at Bristol is top notch. We only found out the RVR was 250m on touch down was when the tower told the aircraft behind. Once you get away with it once there is a tendency to do it again. And if its what you have seen throughout all your career you think its normal.
The UK is actually quite strong dealing with below RVR approaches there is set ATC RT which will be given and if you land anyway the **** hits the fan Most countries this is not the case and if you manage to land nothing more is said about it.
Of course busting DA there is no proof one way or the other on the ground and its perfectly legal to attempt an approach in VV000 550m RVR even though there isn't a chance in hell of getting in. I have always wondered why there hasn't been an approach ban for sub 100ft BKN or vv001 for cat 1 approaches. But if there isn't a robust ATC system from discouraging any attempt pilots will continue to try. To be honest if you had a look at the stats for different airports you might find its normal for local pilots to land in such conditions. And they have been doing so safely for years and years.
And also IOM would be a good place to start. I have diverted from there to Liverpool only to asked by ops why the hell didn't you get in. The Let410 front of us had and the Jetstream behind us even though the RVR had dropped another 100m an the VV gone from 200 down to 100 . We couldn't see Jack at 200ft not even a dim glow of the lights (it was at night) Top cover appeared from the CP and they got told in no uncertain terms to wind their necks in. But if your CP is the sort that he does that sort of thing your stuffed and its time to look for another job which your more than likely doing anyway working for that sort of company.