Seems like Waze should probably try to send thru traffic down double-yellow-line roads. Those roads are typically better able to handle the traffic at least where I live (in Baltimore). Sending folks down a single lane (but not technically one way) street is nuts and doesn't really save much time.
those roads typically have higher speed limits and will be faster routes -- until they are clogged with traffic. Which is when Waze (and, for that matter, Google Maps, and any other traffic-aware routing system) will use alternative routes which are slower in the ideal case, but faster with the actual current traffic loads.
There's ways to avoid this:
(1) Design residential districts so that through traffic is impossible. (Lots of places do this, by having branching patterns rather than grids; this, of course, also makes it more possible for accidents, etc., to prevent ingress/egress.)
(2) Provide capacity on arterial roads so that they don't jam up and leave residential roads as faster through routes.
(3) Improve public transport capacity so that the existing capacity of arterial roads is sufficient.
Long before Waze and similar systems, people who frequently drove in an area would learn over time the alternate routes (including those through residential neighborhoods) that provided better times when main routes clogged up and use them freely. Technology just makes it so that information is more rapidly acquired by commuters. Its irrational, however, to expect commuters that have that information, whether through trial-and-error born of frustration (and then spread through word of mouth) or through modern technology to not use it.
