Cut each artichoke into quarters lengthwise, dropping them immediately into a bowl of water with the juice of 1 lemon, to avoid discoloring. With a small, sharp knife, scoop out and discard the hairy choke.
In a large saute pan, mix the olive oil, vinegar, wine, garlic, parsley, thyme, salt and pepper. Arrange the artichoke quarters in one layer, with one cut side facing down, in the saute pan. Place the pan on a burner and bring the mixture to a boil over high heat for about 30 seconds. Then place the pan in the oven and roast the artichokes, turning once so that the other cut sides face down, until golden brown and barely tender, about 15 minutes total.
The artichoke quarters may be prepared to this point several hours ahead and set aside at room temperature.
Pick up the artichoke quarters (with tongs, if hot) and allow any excess oil to drip away. Grill the artichokes directly over high heat, turning occasionally, until they are nicely browned, 4-5 minutes.