1) Used correctly, Litchi would not cause any flyaway or crashes. But remember that Litchi is an automated system, same as using active track or POI. If you have your Mavic do a POI and it crashes into a tree - it's because the pilot didn't set the right height - not Litchi of DJI Go apps fault.
2) I've used Litchi for many missions and I love it. I first got it to supplement the ability of my P3S drone. With the Mavic I've used it less, but still use it for missions, panoramic, VR, and screen recording.
Looking at the link you gave I can clearly see the issue in the first paragraph - " The mission was a 37,500' non-stop @ 30 mph & the Mavic was out of RC contact for most of the mission." Without any other data, this line indicates the the pilot was clearly using Litchi to do something beyond the means of the Mavic. If the Mavic was not able to fly in the area with the DJI Go app - then you can't expect it to fly with the Litchi app.
So here's what I do when I create missions:
1) Make sure it's within RC range at all times. I've had a couple missions that lost video signal for a second or two, but never allowed it to go beyond RC range. RC range depends on location so keep that in mind. IF you are flying a mission and start noticing you are going in and out of RC range, don't let it continue - put the Mavic in sports mode and RTH.
2) Make sure mission length and time allows for wiggle room. I created a quick mission in Litchi Mission Hub for a 37500 feet at 30 mph and noted the time - 19 minutes. In perfect conditions this might be possible - but I would never fly it. The reason is your expecting it to fly at 30 mph at all times, something that might not be possible. Every time you have a turn in a Litchi mission, the drone slows down to execute the turn. Not only that - you need to factor for wind. If your flying against the wind you'll never get the same speed as flying with he tail wind. Check out a video I made an overplayed the speed info for a mission with 20 mph to see how different the speeds are:
You'll notice on the way out there, it barely kept at 20 mph. Also keep in mind that the higher you go, the crazier the wind can get. Also in some instances, I've seen wind blow the Mavic off course, in which case it stops for a second to regain itself, and then goes back to the last mission point and goes from there...this again could add to the time..
Give that the longest flight I've done on my Mavic is 22 minutes. Having a 19 minute Litchi flight is scary to me. The max time I would have one was maybe 15 minutes if I know I had clear line of sight the whole time, and I would monitor it and take over at the first sign or problems.
3) Always be prepared to take control. Most airliners these days can fly themselves from point A to point B just fine. The pilots are really on there in case of emergency. With Litchi you have to treat it the same way, it's an autopilot for you and if you don't watch it and take control when you need to - your at fault. The easiest way to grab control is switching to sports mode which automatically ends the missions and gives you full control again (assuming you have been a good boy and stayed in RC range). Even with DJI Go, there has been plenty of times when using an intelligent flight mode where I have taken over and flew it out of danger (mostly trees).
At this point, I'm thinking i need to make Litchi series on my youtube channel to help people out. They are misusing it and then blaming it when it does what you told it to.
Btw, my most complicate mission had 25 points, 8 POI, and lasted 14 minutes.
