but
I feel that we all have good knowlegde of what is the out come from all of the pondering! There is alot of good answers and mislead info which leads to confusion for the brain!
A knife-edged crank has few designs for different purposes like for instants first is cutting through the oil for less oil spashing which leads to less drag on the bottom end. Also with less weight on the crank which is common sense the abililty to spin quicker than a stock crank would which leads to higher rpms with no bolt-on needed.
An with all actuality if done right with professional tuning to the ecu the lighter crank will be more durable cause of less stress on the moving parts on your bottom end everyone knows that less weight less problems in a sense of lighter moving parts more power gain, but like stated above if the rods and pistons get to big longevity of the build is less.
To use a lightened crank (knifedged) you really have to do some good reseaching on rods and pistons if you are to use it! In all reality when you knife-edge you are to machine with the crank dampner and flywheel that your going to use in your build other wise your build will be a pour one basically a waste of time just a little fun for a while until your engine blows!!
Initially just by knife-edging you will get more power cause of two things less windage (oil splashing) and less rotating mass which free up loss power so you will make more power you just have to do it right meaning all components have to be blue-printed (almost perfect to none).
Someone mension something about final drive gear 4.4 and 4.9 swapping and a lightened flywheel, it will actually give more power in attributes to torque which contributes to power gains in a build. Some said that it only feel like there builds pull harder cause of the contributions only cause it really does give more power just not in horsepower and it doesn't just rev and acceleration quicker but there is good gains from it!
If you research most of what i'm saying is true!