Brad, I am going to guess you and I would agree on many issues.  I do not see fungicide as the fountain of youth, but as a tool to use when I need it.  I too find it foolish to go spray everything and have no checks, but also find it foolish to not spray when problems are found.

Hybrid selection? Ive had farmers look at my plot results before and tell me that they all did very good.....so why pick a hybrid that is sucptiable that costs the same per acre or more if it has to have a fungicide all to perform? 

 If hybrids XY&Z each yield 200 bushel in your plot, but the data is there to show Hybrid Y will on a 5 yr average yield 208 with fungicide, is it foolish to spend $16 per acre to try to get $24-$32 dollars back depending on $3 or $4 dollar corn.  It could be argued that you still may get zero bushels, but you could also get 30.

Soil fertility - I've asked the lady giving the talk at a CCA CEU workshop that was presenting the data on fungicide trials and they did not get conclusive results on getting the fungicide to benefit the farmers pocket book. I asked if they had soil test data on the trials that showed the gain and the trials that did not show the gain? No soil test data....

I will agree with you that fertility helps with diseases, but is not a cure all for everything either.  The plants on our high fertility farms held off diseases the best last year, but near the end of the season, broke with Northern also.  I sure wish I would have done some more check strips last year on what I thought was healthly looking.

As far as SDS, fungicide will never help you, SDS is a bacteria.  Will reply to more later got to go.