Time's up, folks, put down those durian sandwiches and pay homage to our winner, maverick. He remembered two of the doublets, and came up with a significant improvement on the third, at least an improvement defined as a reduction in the number of links needed. Here is maverick's reply, verbatim:

Witch into Fairy with 12 links:
WITCH
winch
wench
tench
tenth
tents
tints
tilts
tills
fills
falls
fails
fairs
FAIRY

Rouge onto Cheek with 16 links:

ROUGE
rough
sough
south
sooth
booth
boots
boats
brats
brass
crass
cress
chess
chest
cheat
cheap
cheep
CHEEK

I think I have an 8 link version for Winter into Summer:

WINTER
winker
wanker
wander
warder
harder
harmer
hammer
hummer
SUMMER
Hope no-one’s upset by the vulgar word ‘hammer’!

Here's another Carollian challenge. Charles Dodgson became Lewis Carroll by translating Charles Lutwedge into Latin as Carolus Ludovicus, then reversing those names, and translating them back into English as Lewis Carroll. Would anyone care to do something similar with their own names? Perhaps generate the new name, and simply post back the results, along with the language used, for others to attempt to discover what the original was. Convoluted cryptography sounds like a good name for this appropriately pointless endeavour.