>>>Today, Sly is disheveled, paranoid -- the FBI
>>>is after him; his enemies have hired hit men.

From what the article mentioned about him working for two days and then crashing, it sounds like he has bipolar disorder or at the very least is hypomanic which is a form of mania (moving from agitation and activity back to normal behavior). Like you said tho, unless he gets help he's just at the mercy of his illness.