Can you show me the literature that proves AS contributes to stroke? No?
Then saying it does is a load of bullshit. Since he already has a diagnosis of blood clotting, which is not a result of AS use, saying that it did means you are talking off the top of your head rather than from an informed position.
Most recent research (last 20 years) shows that AS has no significant affect on lipid profiles (although this is not true of anti-e's). And no research ever shows that short term fluctuations in lipid profiles, such as those you encounter in cycles, contributes to stroke.