Possible Clues:

• He sips any cocktail that's hard and fruitless
• Like a meaningless pursuit
• On vacation, stay in shape jogging uphill
• Endlessly laborious phases in complex housing strategy, finally
• Of a mythological king of Corinth, seemingly endless and futile
• Like an endless rock and roll performance?
• Weakling loses heart before he comes in to bowl, requiring unending effort
• Denoting an unfinishable task
• Eternally frustrating
• Like tragic character's work? He's in a spy novel