namely because aside from equality all of the comparison operators convert their inputs to a boolean and so cannot be placed in sequence like shown here (boolean compared to, say, integer doesn't work). Boolean equality is the one exception which is what no longer works - so the docs are correct.
Yes, that was poorly written...booleans keep the same type and so can be "chained" while other types do not. But precedence is not based upon type, just the operator.
