Now, however, my DQ is of limited value and a rebid of 2S gives a better picture. Qx will be a stop most of the time. 2S. We have a pretty poor 16 count here, and since 2S is allowed to be weighty we have no guilty feelings bidding it here - except that 1NT might be the right spot. Descriptive and positional. This is clear.
Partner can checkback for three card spade support.
Even if partner doesn't have any diamond help, North might still underlead his D AKxxx if I bid this confidently. I think 2D should show either a stronger hand, or better spade support, so that's why I can't bid that. In general, I think partner would double with four spades so 1S should show five. Our values justify a cue-bid in support. This is middle of the range for this bid in a five card major weak-NT system, where 1C must show a good hand, and 1S should show no more than a decent four card suit.