It was discovered by these two athletes that you really can't fake a hundred miler. One might be able to fake the first 50 miles or so, but after that, it becomes a Death March just to get one's burning chest and phlegm-filled orifices to the finish line. In fact, this trying experience even left one (normally fairly enthusiastic) athlete to proclaim she's done, she quits, no more racing ever again. (She has since decided she might be convinced otherwise).
Thus, the official CD advice is as follows: When faced with the common chest cold, feel free to race any distance up to and including 50 miles. Just don't venture beyond, unless you want to be left coughing up large UPhO's (unidentified phlemgy objects), and clinging to your little furry friends immediately after the fact.
Or,perhaps, just haggard and like you need a cookie.