That's what some of the filters like TR only, most helpful, courses played and years of experience are for, you can sort out reviews by more experienced players and reviewers and generally get a lot of the better ones to the top.
I think those filtering options(except years) to some extent work against those who are just starting to write and may have something good to contribute. For instance, I have 23 helpful/3 not helpful---on 22 reviews, most of which have been up for 4 months. It seems to me I write well, but getting noticed is difficult.
I got 4 :thmbup: for the course I've rated the worst so far---1/2 disc for New Plymouth, yet its my shortest, least literate review. Go figure.