My partner sitting South (a regular poster here) chose to ignore the spade suit and instead made the 2/1 game force response. This made it easy to bid the good 6♥ contract. Of course had I held a hand with 5 hearts and 4 spades, we would miss the 4-4 fit and possibly the best contract. Also the 6♥ looks to be jumping the gun when 4NT will find me with ♥AQ plus the known ♦AK and then slam can be seen to depend on ♣A right or ♠K onside.
Later I thought how should we have bid the slam? Getting there with any degree of confidence looks virtually impossible to me.
1♥ 1♠
2♦ 3♣
3♥ ?
Say you go through the 4SF route with 3♣. Partner makes the 3♥ default denial of a stop in clubs and more than 4 diamonds. Now what can you do? Is 3♠ showing 5 spades or could it be showing a control and agreeing hearts? Or either? Partner could have 5 or 6 hearts, you don't know. Say you decide to make the murky 3♠ bid and partner next bids 4♦. Presumably you would take that to be a control bid. Now where do you go? Partner may be ♦K less than he is.
My ramblings are making me think that partner might be doing the right thing in setting the game force at the 2 level. The downside is that a missed 4-4 spade fit could be a better slam bet than the known 5-3 fit, but that risk is small.
Any opinions? Any suggestions for bidding the slam?

Help

Actual bidding:
1♥ - 2♣
2♦ -2♥
3♦ - 3♠
4♦- 6♥