Possible Clues:

• Playwright
• Writer agitates mad artist
• O'Neill or O'Casey, for example
• Wee tipple one's introduced to a teetotal writer
• He mixes work and play
• Coward, for example, showing mad traits after breakdown
• Foolishly admit star, one creating theatrical scenes
• One making play having drink with a bird consuming seconds
• He skilfully mixes work and play
• Writer's short, right out of Toulouse-Lautrec, perhaps