>I always tell my Jr. Engineers that if you have to work THAT HARD to accomplish your daily tasks then you need to go back to school or go for a more newbie-friendly position.

I don't think that this is very productive thing to say to someone. If the Junior Engineer is still able to produce, why do you care how much they struggled with it? If a person truly wants to grow and then struggling on problems that are on the edge of their comfort zone sounds like the perfect way to do it.

If their abilities are effecting project timelines, quality, profitability, etc then I can understand having that conversation with them but I really don't see the harm in someone challenging themselves professionally.