My Personal 92FS has been to see Ernest Langdon @ LTT & it's DA pull is sweet & smooth, Not blocky like it was before I sent it to Him..
I have the D spring in it for self defence purposes, I have a lighter Competition Spring that He sent me as well but I've never installed, Didn't see a need as mine is so smooth..
The D hammer spring does make a big difference in DA & SA pull BTW..
I wish I could tell you what LTT did to mine to make it smooth, But It's hard to tell, He did fit all the parts & polished key areas within the trigger mechanism, Trigger pivot, Trigger bar, Hammer, Sear etc, I opted to go with my factory trigger without trigger stop because I planned on using it in Stock Pistol Class at the range..I now wish I had the speed bump trigger with less overtravel..
It could be that the hammer stirrip is rubbing inside the spring, Did you oil the spring? You can also smooth out any burs on the stirrip with a piece of 600 grit silica carbide sandpaper..