I've been playing the game only for 2 months now and every time I think I've got the hang of the rules I find something new. Even my highlights now need highlights.
You have a long journey in front of you, grasshopper. Some of us have been playing for 10+ years and are still finding new things in the rules... *sigh*
Anyway page 32
How are these parts of the rules meant to be read?
Interpenetration can go through a single corner or straight forward/back with a list of conditions.
Yep.
The next paragraph states that spontaneous advances can pass through any friends in their path (with a few exceptions)
Yes. But note that those exceptions are important.
Are the spontaneous advance interpenetrations limited by the paragraph above it or is it a stand alone paragraph and they do "pass through any friends in their path" (implying in any direction)
It's a stand alone paragraph. If you look at the interpenetration dot points you'll see that each case specifies the type of movement which can make use of that dot point's interpenetration. Thus, for example, the interpenetration provided by the second dot point is available only when doing a repulse move.
I have been interpreting it as a stand alone paragraph so that spontaneous advancing troops just barge through. However, on page 30, in the 4th bullet of the penultimate paragraph it states that a spontaneous advance stops when it contacts troops it cannot pass through.
Yes. This is because of those important exceptions - there are some cases where troops can't be passed through by friends making a spontaneous advance. For example, if you have troops in combat (or able to provide rear support or overlap support this bound or next), then impetuous friends won't pass through them - they're stuck behind.
The same goes for impetuous troops which have already made a spontaneous advance this bound - impetuous troops won't pass through them either. This is particularly relevant if you have a whole bunch of impetuous troops, especially if they move at different speeds. Imagine you've just broken an enemy command in your opponent's bound, and you now roll 1 for PIPs and lose control of the victorious elements in your own command: up front you have the slow-moving heavy infantry making a fairly slow spontaneous advance, and a short distance behind your light horse reserve also goes berko...
So you do the impetuous moves of the heavy infantry first, then you do the impetuous moves of the light horse. So the LH stop when they contact the heavy infantry which have already made their impetuous moves.
But if you did the impetuous moves of the LH first, then they'd pass through the heavy infantry, which would then (second dot point) "follow behind in spontaneous advance".
Does this make sense?