re: Your 'IF' is not plausible: Why not? Here is the correct reply
Wickramasinghe and Hoyle never said anything about "life forming" anywhere (shows how much you know R.L.) in the universe. All they have said is that it is transported throughtout the cosmos as lypholized spores incased in the ice of comets. If rocks are a good mechanism for transporting microbes from one planeta to another (given certain parameters) then why how much more protection would life have inside water ice comets? Since the theory is still in dispute, to shrug it off on a whim shows arrogance and lack a of scientific curiousity.
Of course there are those scientists that profess to know it all. Real scientists -- don't know it all, and is why they are scientists. Only braggarts know it all.
BD