Every airline has their own policy in this regard, and that is to be respected of course. I have done very few intersection departures in my time, but those I have done are like I used in my example 1,000ft down a 10,000ft+ runway. With our policy that this means no thrust reduction such a takeoff is normally far less limiting in performance than a full-length departure (V1 will be reached much sooner).
Do bear in mind this is not typical procedure, like I say I have done this only a handful of times (mainly so that we don't miss our ATC restriction, so we need to "jump" the queue of departing aircraft at full length). This could avoid a long wait for a new slot at some times of day, not what you want with the engines running at the end of the active...
As far as reduced power take-offs go, like you my airline stresses that every bit of thrust reduction will go a long way to preserving the life of our engines. We always reduce take-off and climb thrust wherever we can, despite the increase in trip fuel burn and noise footprint that this creates.
Our calculations under JAR for reduced thrust take-off require that ASDA is greater than or equal to ASDR. (Accelerate-Stop Distance Available is greater than Accelerate-Stop Distance Required, for those not familiar with the terminology). That is assuming our ASDR is the sum of the following distances:
(1) Acceleration on all engines at the take-off thrust setting to V1
(2) Further acceleration with all engines operating for a further 2 seconds
(3) Full braking and speedbrake for the aircraft to come to a complete stop, assuming any deceleration is not initiated until the end of (2) above.
Reverse thrust does not come into the equation.
Since in reality we are not going to take 2 full seconds to initiate braking action after passing V1, and that we will in reality use full reverse thrust on all (available) engines, there is a good margin of safety built in to the calculations.
Our company also stresses that a take-off with maximum derate can be just as limiting
in runway performance as a max-weight departure.
"Improved Climb" with excess runway is not a procedure I am familiar with. What does it involve exactly? I recall discussing something like this with regard to PIA 747 departures from Manchester (using up more runway than you need to attain a higher rotate speed?).
Personally I didn't see how this helped improve the climb, perhaps you can describe the procedure better?
Happy contrails Captain
I used to love the smell of Jet-A in the morning...