What is said isn't useful or right
I attended a presentation by a commercial enterprise and it is interesting to note how little university research was cited. I think this is because university research does not support all the recommendations. All the recommendations involved spending more money and buying more inputs.
I know that some of the supporting information given was not applicable to this area. It is right for other areas, but not ours.
In many cases, the recommendations might add to yield but won't cover the cost. The dealer can always say, "well you got more bushels, didn't you?"
Re: What is said isn't useful or right
I have been to field days like that. While $6 corn may justify some of these things, they were recommending them back when corn was $3. I'll never forget once when the seed salesman gave his population recommendation, and the agronomist standing right next to him said 'Why plant so THICK? You are planting a population for 250 bushel corn on 180 bushel ground. Save yourself some money, and back the population 5,000 and you'll still get as good a yield."