[Tutor] s.insert(i, x) explanation in docs for Python 3.4 confusing to me

[boB Stepp]

At https://docs.python.org/3.4/library/stdtypes.html#sequence-types-list-tuple-range
it states:

"s.insert(i, x) inserts x into s at the index given by i (same as s[i:i] = [x])"

I find this confusing.  First, at the interpreter, whenever I type in:

>>> things
[0, 'Hmm...', 3, 'WhackABunny', 6, '?']
>>> things[-1:-1]
[]
>>> things[0:0]
[]

I always get an empty list, which is actually what I was expecting, so
I do not see how s[i:i] can ever equal [x].

The second thing I find puzzling is the docs say x is inserted at
position i, while in the interpreter:

>>> help(list.insert)
Help on method_descriptor:

insert(...)
    L.insert(index, object) -- insert object before index

The "...insert object before index" makes sense to me, but "...inserts
x into s at the index given by i..." does not because:

>>> things.insert(-1, 'What the heck?!?')
>>> things
[0, 'Hmm...', 3, 'WhackABunny', 6, 'What the heck?!?', '?']

"...at the index..." to me would mean that 'What the heck?!?' should
become the last item in the list.  Again, the interpreter help gave
what I was expecting.

Am I just being dense or are the docs in this instance confusing?

-- 
boB