Started running again last night. Will be once every 4 days for two hours like I once did. Just did an easy 40 minutes to start.

The pros are:
1. It adds a dreamy quality to life being able to run at a decent speed for two hours straight without getting tired.
2. I'm getting a bit of chunk I really ought to address.
3. Like it or not we are creatures of flesh and blood and things like running long distances are ingrained in our genetics.

The cons:
1. Time. I have maybe 30... 20 free hours in the average 4 day span. (Well a lot less right now. But eventually will have something like that.) Giving up 2 hours to something that seems a tad ridiculous is an issue.
2. My ego gets in the way and I go too fast and it can end up being torturous at times. I remember the last really good run I had... The first hour was bliss; just floating along at a good pace like I wasn't mortal. Not even the slightest discomfort. And even just the bounciness is discomforting to the normal person BTW for running a few seconds. But I had the proper gait that was so smooth.

But then from boredom I'd take a different route every time. And this time I hit a hill that went for 15 minutes straight. By the end of it I'm afraid I was shot. And I guess I had gone too fast. Then I was still at least 5 miles from home and I forced myself to keep running at a decent pace for that 5 miles and it was torture. 4 days later I just didn't want to do it again with that memory in mind.
3. Injuries. Mostly not an issue for me. I run/jog like a sprinter does. Very smooth and flowing. Plenty of calf use. I did most recently experiment with a more economical typical stride. Cloppety clop. My knees and hips started hurting. But with the correct smooth almost ballet like stride up off your heels I think injuries are not an issue other than a potential pulled calf muscle.
4. To consistently go every 4 days I'll have no choice but to have days where combined with work it is not possible to get 8 hours of sleep. I've decided occasionally getting an hour or two less isn't the end of the world.

The thing about just doing it every 4 days is that actually the important part of running is having adequate muscle development. As far as being any good at it, it's a matter of having a good strength to weight ratio in the right muscles. People instead think of it as primary a cardiovascular exercise that should be done more often. As far as being any good at it, it should be treated like a strength training exercise and thus more rest seems to be needed.

At least that's what worked for me. Trying to do it the normal way never did me much good. Certainly never experienced that blissful almost immortal feeling with shorter more frequent runs.

It unfortunately has to be it seems at least two hours. This I experimented with much. I have done a ton of experimenting with exercise over the years. Two hours is the minimum that your body gets the message that this is something it regularly does and thus ought to get better at. Or whatever.

I recall a guy who would run a marathon every single night. His wife didn't care for the time he spent (210 minutes each night), so he waited till she went to sleep. He almost solely ate pork chops and orange juice. He had a debilitating stroke at 62 and died at 64.

I recall the Taramara(?) Indians who once a week, once every 4 or 5 days... Will run for 12 to 36 hours straight. They used to chase down food this way; run it to exhaustion. Now they do it more as a game. It can be a blissful thing to run for extreme distances. But at the same time such a waste of time.