Of course he had someone feeding him. Goals frequently have assists. I mentioned Dvorak's superior goal scoring numbers because goals are worth more than assists. With 2 assists often being awarded for a single goal, don't you think a guy who scores more goals than another guy, while also having more points, was the better offensive player?
Marner did step up in a big way in the playoffs. So did Tkachuk. If an amazing playoff run makes Marner the next Patrick Kane, Tkachuk must be the next Jamie Benn. Or perhaps a small sample size of domination should be taken with a grain of salt, especially when compared to a much larger sample size of lesser production.
Like I said in the same post, I don't think Dvorak is a better prospect than Marner. Having said this, I don't think the difference between the two is monumental. Dvorak probably ends up a 50-60 point guy with a great two-way game. Marner probably ends up a 60-70 point guy with little impact beyond offense. Not exactly a huge gap between those two guys. The difference between Dvorak and Marner only seems huge if you think Marner is a future PPG superstar, which I do not.
In regards to your Brown and McDavid example, my point remains the same (even if your comparison is ripe with hyperbole). I don't think Brown is a better prospect than McDavid, but he was the better player in 2014. And it's worth mentioning that Marner is not comparable to McDavid in any way, shape or form.