a very reasonable analogy Deist. 
rlQuote:Science can find and interpret circumstantial evidence which may tend to support the possibility (or not) of such and such event occurring in the past. 
 . ANother beauty of "circumstantial"evidence is that it must be severally reinforcing sort of a "web" of reinforcement. One piece of evidence  never good enough. Several layers, all reinforcing are required, and these, in turn, are each separately reinforced by yet other data.
I think the present argument of the significance of the Chixclub is a perffect example of how further evidence reinforces or causes re-evaluation of an explanation. There is no doubt that the Chixclub occured, we have a crater (after many years of searching) we have "the dusty fallout" , we have a worldwide layer of ash, iridium , and tektites. Weve located tsunaki deposits contemporaneous to the event. We also see a "great dying" of certain species consistent with the occurence of the event. What the latest controversy is revolving sbout is whethere this "great dying" was actually caused by the bolide. Or, as is being revisited by Gerta Keller and some others, perhaps the extinctions were more a consequence of volcanic gases and changes in oxygen levels. The chixclub event is actually traceable in the center of the Deccan basalts. and life (including dinosaurs) were found to have suffered little by the bolide but were more affected by the continuous flow of the very basic lava . Now, there is abundant "cicumstantial evidence" supporting all the findings. We have a clear event, at a known time, another similar cataclysmic event , also at  a similar  time,then we have a consequence to lifes continuation and development. All based upon circumstantial evidence. 
I have no problem with the strength of "circumstantial evidence" especially since its reinforced by many layers of the data web. I think thats where you fail to understand  or recognize the  strength of all this evidence.