This was one hand from the club tonight. The play went a club lead taken by Ace, DA, S to King which got ruffed

Partner was North and was adamant that his 5H is the correct call - "4-4 fits play better than 5-3 and the singleton DA is a miracle". I'd have bid a simple 3S "to save space". We were both tired and under time pressure :/
Any thoughts on the correct bidding sequence here? My attempt would be ...3S-4D (cue)-4NT-5D(0 or 3)-5H(Q ask)-6S (yes but no K). Perhaps this isn't ideal as it ignores the heart fit?
ahydra
edit: ARGH sorry forgot to put system. Acol with 3 weak twos and a weak no trump!