[cjy]

The first quote wasn't an ad hominem attack because it wasn't directed at the engineering deans, but rather at the author. If you're trying to determine whether people should drop out of school why would you only survey deans to make a point? Moreover, it is perfectly valid to note the conflict of interest a speaker may have. Their incentives don't make their arguments wrong, but it should give us caution before making generalization or relying on their expertise.

I think we're talking past each other to a certain extent. The deans do make some good points. 1-4 are generally true. I just don't think they are sufficient evidence to show that students shouldn't drop out. They are saying that colleges are good social networks and send important signals to employers. My argument is that something is wrong when we are spending 100K on a screening/networking mechanism. Notice that none of the deans said stay in school because of the things you'll learn in the classroom.

[dlo]

"Notice that none of the deans said stay in school because of the things you'll learn in the classroom."

The second-to-last paragraph of Jim Plummer's response seems to say so. Example: "A university education gives the large majority the tools to become innovators and entrepreneurs throughout their lives." He then goes onto extol the benefits of an engineering education even for careers outside engineering.

[grav1tas]

Your suggestion that the deans are pro-college institution because they are deans doesn't necessarily follow. It actually is an ad hominem against the deans because you're trying to weaken the author's point by reducing the weight of a series of supporting claims made by the deans because you claim that the deans are acting out of self-interest (or interest of some educational-industrial complex of which they are a part) when they wrote these statements. Given that one side of this argument likes to frame the educational institution as bad (and sometimes go as far as saying the people in the institution are actively working to further its negative ends), it would be reasonable to interpret your first remarks as an ad hominem attack.

That said, your initial statement doesn't necessarily follow because it could also be the case that the deans became deans because they earnestly believe in the system they're helping to further, and that's why they became deans. Claiming the possibility of bias doesn't entail the presence of bias.