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FP2: The conditions for a "dimple" (Polar Coordinates)

Hi,

The edexcel textbook states that in order for a graph of the form r = a(p + qCosϴ) to be in an 'egg' shape p >/= 2q. However, for it to have a 'dimple' q </= p < 2q.

I encountered a question about drawing the curve r = a(1 - Cosϴ). p = 1, q = -1
My issue is when drawing up a table of values it does indeed have a dimple, despite that (using the p >/= 2q rule) 1 >/= -1.
Additionally, for the other rule, it is not true that -1 </= 1 < -2, because 1 > -2.

This suggests that the rule should really be |p| >/= |2q|. Is this true?

Or I've messed up spectularly somewhere and may need some guidance.

Thanks!