I don't know about you, but I have a hard time fitting all my runs in. Sometimes it's because I'm scheduled up to my eyeballs, other times it's because I blew off a run early in the week and then get caught up with shuffling things around to make my remaining runs fit.
This week, for example, I had a work event Tuesday night. Wednesday, I ran just 3 miles, testing out the ITBS, felt fine. Last night, I stopped by my Mom's house to help her w/ something and of course got persuaded to stay for dinner - and I'm sorry, but I can't really run after a steak dinner. Now here it is, Friday afternoon, I can run tonight and tomorrow, but have houseguests arriving at noon and won't be able to run on Sunday.
So, I'm doing my long run tonight (8 miles), and will try to do 3 tomorrow a.m. I've never done an evening long run followed the next morning by short distance. I'll report back on how successful that is. :-)
If nothing else, shifting my long run to Friday THIS week helps w/ next week's scheduling. I'll be on the road starting next Friday a.m., so will do my long run on Thursday. Phew, too much to think about this far in advance...