Very sad news. One of the books on my shelf that I will not let go is his "Life at the Limit" which is a great, if sometimes a bit gruesome, read. One interesting that comes out of this book is the support he had from Bernie Ecclestone at a time when safety was not even thought of. BE forced the circuit owners to provide the facilities required, anything that Sid Watkins asked for BE provided.
The only failure that Sid Watkins had was not being able to persuade Ayrton Senna to go fishing with him rather than race on that fatal day. What a shame Senna refused.