I have run commute many times to various places down the years. Mostly from my home to work about 7 miles away on and off for a few years. Also to another place about 14 miles away, when I would get the train in the morning, with 4 miles running and then run home in the evening. I found it tiring and only managed once a week but great time saver for marathon training.
I worked and lived away for a few years in Oxford and Cambridge and found digs about 4 miles from work and could manage the run commute twice a week, (say 16 miles). My favourite was rural Oxfordshire. I stayed in a farm house and ran through the cherwell vale. It was bliss in on summer mornings, down quiet lanes and footpaths, over rivers and streams and grand union canal. Once met some aggressive cows and chickened out from their field and made a detour. Glad I did based on stu comments. I did not know they were so dangerous.
I would have breakfast of porridge and start the commute run very gently, slow walk or jog for first mile. I think the twice a day run was a great bonus for the marathon training.
Do you run both ways - to work and back? I recommend you do.