The whole concept of introductory courses as "weed-out's" is repellent to me.
How about the concept of intermediate courses as "weed-outs?" At some point, you have to separate the ones who are serious about the subject and those who are just there because they don't know what they want to do for a career. Better to find out sooner than later. I was "weeded out" from the accounting major by the time i hit junior level and let me tell you, i am very thankful for that.
The only thing i find "repellent" about "weed-out" courses is when i am required to take one in my minor field. Other than that, a teacher can only provide so much guidance and encouragement -- they simply cannot be expected to do the work for the student.
You know what they call weed-out courses in the real world? "You're fired!"