In Its 52nd Year, The Venerable Tack Room Once Again Wins By A Length. By Rebecca Cook ALTHOUGH I'VE ENTERED into some pretty hallowed halls in my tenure here, I'd never had the pleasure of supping at The Tack Room, perhaps the city's most celebrated restaurant. Since its inception in 1947, The Tack Room has racked up more awards, distinctions and accolades than is reasonable to expect from any dining establishment. How I managed to sidestep its welcome mat for all these years, I'll never know. Now, however, my résumé as a Tucson epicure is complete. I have at last been to the sacred mountain. And it was