I doubled back in my configurations last year with my Premier 1 Poultry Plus 48" netting, no problem. Check it with the meter (you have a meter?), you'll see it's fine, as long as the hot wires (everything except the bottom-most horizontal wire is hot on this brand) don't lay on the grass at all. In fact I bunched it up twice as I recall, sort of piling it all together on it's own posts, gently looping the top and side wires, and sometimes using an extra Fiber-Tuff post to help hang the extra fencing at the right height.
Depending on your setup - the size of the battery and solar charger and what it puts out- that determines the length of fencing you can run on it. I have their IntelliShock 60 solar thing. I think it is 0.5 joules. I think it can run a max of 350 feet of 48" fencing, I asked on the phone once for what I had. Of course, the longer it is, the greater the chance a cumulative draw of any grass or weeds that touch any hot wires will lower the zap level.
The zaps have their own timing. Just like jumping rope you can gauge it and work with the netting in short bits without turning off the energizer if you have to. I have hand-weeded that way when I was quite far away from the energizer and happened to see a weed. Also, you can hold the post in between the hot wires. You can hold the vertical wires. You can wear dry leather gloves too and that is quite good. For access right now I made a cloth loop from the end fence post to a big FiberTuff post, and the net posts are flexible, so I unloop the big post, and step through in between zaps by gently pulling it away. Sometimes my butt gets a little zap through my pants! But not a big deal. I just make sure my cell phone is not near the fence side. I also bought a gate I'll install again for the main summer area, they work very well and are one-handed.
Emergency access - in an emergency you won't care, and it won't matter. You will not be injured or seriously hurt. You might get lucky and blast through the net in between zaps. Anyway, if you are wearing clogs or boots or sneakers, so are not making a good ground, you are fairly well protected from any serious zaps. (I have felt both - wet feet, wet hands and hot wires gives a real good one, but not enough that I wouldn't continue through in an emergency.) Do not lay down on the hot net, or place your neck or head on the hot wires, and you should be fine. I suppose if you have a pacemaker there might be special guidance.
Edit to add: I bunched up when I was going through areas of lots of rocks and the step-in posts were tough to do, there'd be great soil and then a rock, darn! Sometimes I used a tent pin to drive holes first. So if I didn't need the extra length I bunched rather than keep setting posts for no reason.