Investigate Unmeasured relays that get the Fast flag

I was looking at some consensuses today, and I noticed that there are many Unmeasured relays with the Fast flag, which doesn't seem right.

For example, in valid-after 2014-08-17 12:00:00 we have:

r k33ac R5oMCf+qgKvU/WE6nmB5/7/Vhlc E3tqtWZ92BE1vbOP4Wg1PKp241c 2014-08-17 02:11:59 50.38.49.173 443 9030
s Fast HSDir Running Stable V2Dir Valid
v Tor 0.2.4.23
w Bandwidth=20 Unmeasured=1

This is an investigative trac ticket, since I'm not sure if this behavior is a feature or a bug yet.