I imagine that the force vertex produced by a chin strap would be up and backwards. I don't think that'd be healthy for the development of the face, especially for people with malocclusions like an overbite. If you've got a retruded mandible in relation to the maxilla, you probably don't want to encourage it further back. The chinstrap could also possibly reinforce a bad habit for clenchers.

Everyone always thinks mouth taping is dangerous. But these are always people who have never tried it. 
What are you afraid of? Suffocating? You will wake up and rip the tape off. It’s also not likely that you won’t be able to breathe through your nose at all. The tape comes off easily unless you use duct tape or something. You could probably even breathe through it if you absolutely had to, or the pressure of your inhale would suck some air through the sides. 

the only other potential problem is vomiting. And when was the last time you or someone you know vomited in their sleep? Probably never. The only reason this would happen is if you were severely intoxicated or had a medical condition that could cause you to vomit in your sleep. If either of those are the case, then you shouldn’t be mouth taping. Otherwise, it’s completely safe and much more effective than using a chin strap. 

mouth taping doesn't work for me.
if i pucker then tape it causes visible buccinator hypertrophy, and might worsen my sleep apnea, if I don't it doesn't work at all and i just suck air throught the gap.

also lip pressure all night can't be good for teeth

@fanaticmind

also lip pressure all night can't be good for teeth

I think that a good lip seal entails some pressure on the teeth, accomplished through gentle suction. Proper occlusion would then counter-balance this.