Hi incisor, yep that’s the impression I get.
You can take a deep cycle safely down to 20% ( 11.58 volts ) without immediately damaging the battery but the number of times you take it to 20% will have a bearing on shortening the useful life of the battery as compared to only taking it to 50% ( 12.06 volts ) and only taking it to 80% ( 12.42 volts ) will, in theory, give your battery a longer life span. Now here’s a catch and may go some way to giving matbor an idea why some people say you should deep cycle the battery every so often.
If you only ever take the battery down to 95% then you will actually shorten the battery’s life span and before you ask, I don’t know why and nor do I care, because if you only ever take your battery down to 95%, WHY DID YOU BUY SUCH A BIG BATTERY IN THE FIRST PLACE.
Deciding on how far you discharge a battery requires a whole host of factors to be considered.
First and foremost, if you are planning on using it only 6 or 8 time a year and take it down to 20% of charge then you can, in theory at least, expect the battery to last only about 4 years which is probably about the normal life span anyway.
Whereas if you intend to use it every weekend than you have to make sure, to get a reasonable life span, you don’t take it below 50%.
I stated “ in theory “ because there are so many other things that can have a major influence on your battery’s life span such as how quickly or slowly you discharged it, how soon you got it back on a charge voltage and how quickly or slowly you recharged it and so and so.
The point is, each individual’s use of a battery will have the greatest effect on how the battery performs and lasts.
Hope this helps and I thing I have worn out my typing finger. 8O
