Not vulnerable versus vulnerable, I was sitting third position with the following hand: (s) KQx (h) --- (d) KJ9xxx (c) K8xx. (All x's are 7 or lower.)

I opened 2D, a "weak two" after two passes. One of the opponents protested that my holdings exceeded the 6-10 hcp point range for a weak two. Technically, I had 12 hcp, but I downgraded my hand for the following reasons:

1. I subtracted 1+ points for the lack of aces and Ts.
2. My KQx of spades was a "clunky" holding whose true value was closer to 4 points (a single ace) than 5.Between this and 1), I adjusted the value of my hand to 10 hcp.
3. My lack of hearts meant that the opponents would have a heart fit unless partner had six. A bid of one diamond would be easily overcalled 1H, an opening bid of two diamonds would have some preemptive value.
4. Partner either had less than six hearts, or if he did have six and passed, he was very weak, meaning that with my RHO also having passed, LHO (fourth seat) would be very strong.\*

The opponent felt that my bid preempted partner. I said that I have "barely" an opening hand (with a minor suit), and partner's pass said he didn't, so I had little fear of missing game. Was I really too strong to open one diamond instead of two?

\*If I had 12 hcps in say first seat, I would attribute an average of about 9 hcps to the remaining three players. With two passes to my right, I guessed that they would average 7 hcps each, 14 in total. Adding 12 for me would leave 14 for my LHO, and most finesses would be "onside" for him.