Win for the system

One of the systems I play with my current partner I designed wholly myself. It's what we do after we open our weak NT. I find system design fascinating, the whirl of trade offs: efficiency, memory load, naturalness, legality, safety, frequency, pre-emptive nature... make it practically a game in itself.

One of the noted problems with 'normal' systems over 1NT is you can't stop below 2NT when partner invites. Usually this doesn't matter but sometimes you find that 2♦, 2♥ or 2♠ is a great spot and 2NT is unplayable. Here's a hand that came up playing in the South Island pairs yesterday (largish and importantish):

♠ T 6 ♥ Q J T ♦ A J 9 8 6 ♣ A 6 5		♠ 9 4 ♥ K 8 7 2 ♦ K 4 3 ♣ K Q 8 2

The west hand opened 1NT weak at every table that played one. At some tables the opponents helped out by bidding spades aggressively stealing away the contract and probably going down one in 3♠. But at others the auction was invariably 1NT - 2♣ - 2♦ - 2NT - pass which fails immediately on a spade lead and the opponents get another shot when the Q♦ is offside. At my table the opponents were silent and we bid 1NT - 2♣ - 2♦ - 2♥ - pass. On generous defense this made +170 but +110 is almost certain. Let me explain, 2♣ was invitational and 2♦ said no. If I had good diamonds here I would pass but as it happens I can suggest 2♥, partner liked it and there we stopped.

How would you have bid the hand? If you play a strong NT move the K♣ to the other hand, now what would happen? Are you wallowing in -100 or safely in a suit at the two level?