OA - a most balanced and unemotive post. Something of a rarity in this thread! MG being pedantic? Never...!!
However, a few comments if I may. The Merlin does "wheeze" if Afg (compared to Chinook or Puma 2) but will be a revelation to the CHF at Sea Level and near ISA temperatures. The Merlin is a huge fuselage and, yes, does have a slightly smaller footprint than Chinook, but LitM is all about punch per deck spot - you may get 5 CH47 instead of 6 Merlin on a CVS in the LPH role but those 5 Chinooks will be packing 40+ marines or underslinging the Viking - and to be frank, no amount of fettling the Merlin engine/Xmsn system is going to get the Merlin there. WRT downwash - I've flown the Chinook embarked and it was most uncomfortable being on the deck with a Mk1 Merlin landing on in front of me - subjectively it was far worse than another chinook; perhaps a function of disc loading?
Perhaps the biggest point I'd make is that nobody was really complaining about Transition when the RAF were getting 24 new CH47s and 30ish Puma 2s - everyone got what they wanted. The reduction in CH47s in effect robs the RAF of an SH Sqn (and the valuable SO1 command position) and may lead to a few pilots being without chairs when the music stops. The reason for an upsurge in angst is the uncertainty over Puma 2; the RAF will be vehemently opposed to losing another 2 sqns if it's scrapped. The arguement will be why pay the costs to, potentially, make 2 sqns of trained Merlin aircrew/maintainers redundant and then pay to convert CHF crews to the ac? What's harder - teaching crabs to float or SK4 crews to fly Merlin? Having gone through the former with the CH47 (and being a graduate of the AOPC) it's probably the latter. Whisper it quietly, but landing a powerful, controllable modern helicopter on 20 000 tons+ of steel actually isn't that hard...took me a couple of sim trips and a day/night qual. Within a couple of weeks we were doing AR5/NVG decks. Don't get me wrong, landing a grey lynx on a T42 in the middle of the Atlantic is completely different - but the essence of LitM is that you're close to shore in calmer waters, flying modern ac off large platforms. Speaking to my CHF mates, it seems that there is a massive gap in deck time for anyone who's spent less that 5 years in the force due to Afg - so there's less of a current capability to transfer. My biggest concern, however, would be losing the senior CHF staff's experience in planning LitM ops - how willing will my fellow crabs be in learning the complexity of unpacking an Amphib group's holds in the right combat configured order?
So the arguement distills to how much Defence values a 24/7 LitM capability and the (hoofing) ethos of CHF to deliver the capability. If the answer is "nice to have" then CHF goes and StOM/LitM is delivered by a TAG of RAF CH47s/Merlin and AAC Wildcat/AH. DRWCS will report soon and, hopefully, all will become clear. However, there comes a point when whatever decision is made we in the military need to come to attention, snap a salute and carry on.