I find that with a large enough sample of reviews and some discretion, I can usually make a decent judgement of a property.

The most credible I find usually make very specific praises/complaints and reference the room/service level. A property can be a very different experience depending on standard room vs superior/executive vs club floor vs penthouse suite.

My own review history (14 now) probably would look suspect, as I give mostly positive reviews averaging 4/5. I attribute this to the literally painstaking effort I put into finding the right property for me. I also take into account the star level (a 3* has a lower threshold to meet than a 5*). Sometimes I wonder when reading the reviews, "Did you not even give the hotel's website the most cursory glance?" I swear, some people don't even try.