Sounds like the extended range EOL on a Gazelle - droop the Nr back from 380 to 330 at 90 kts, it certainly made a difference, you just had to remember to recover the Nr before the EOL itself.
Having done both, I recall the Whirly as more "interesting"; the aircraft really "wobbled" its way along in the range auto configuration; I remember it seeming to rock from side to side but then it went noticeably further. Yes, the RRPM definitely had to be recovered (to a heady 230, iirc) before the final landing.
After my B2 - B1 check ride on the Gazelle, my CFS examiner (Dennis H) told me that now that I should always remember never to trust a student because any of them would be capable of trying to kill me! He recalled his time as a newly qualified instructor on the Whirlwind and how he got into the habit of feeling for the collective towards the final part of EOLs being flown by his students (didn't we all?).
However, on one memorable occasion he thought that things weren't going quite right early on during the autorotation. He felt for the collective and couldn't find it! He then looked down and saw that it was almost fully raised and his hand was well below it; he was feeling thin air. Meanwhile the RRPM had reduced to very little and was still going down. The aircraft went in, out of control, from a hundred feet or so. Thankfully in a Whirlwind there was a lot of aircraft to act as a crumple zone below the pilots' backsides and they both survived. Never forgot that sage advice...almost forty years ago now.
