Like a few on here I spent most of my working life in civil aviation and, it should go without saying, am familiar with the principles of descent energy management (or should that be 'decent'?).
Yes, of course, under appropriate circumstances, one can, e.g. having failed to obtain further descent clearance, reduce ROD and speed and then, when cleared, accellerate with a transient increase in ROD.
What if you have been allocated a speed by ATC or are approaching min speed? Well, then you have to apply power and put unwanted energy into the system which will, at some stage, require removal.
Suppose you have the choice of speedbrake or extended routing to lose altitude; remember this: during the increased time of extended routing your engines are still using idle thrust fuel.
I now fly only as a passenger and it worries me that my PiC may think that speed brake = loss of face. I'd rather it was used when NECESSARY - you'll know when that is. Don't let misplaced pride get you into a rushed approach.
Finally, when landing easterly at LHR could you all please arrange to be at idle thrust and on or a little above the path when turning base from the north?
Bas, Marlow.