What is the difference between 古怪 and 古里古怪? According to my book, there is a pattern for building further adjectives from adjectives.
If the original adjective is AB (two different characters), its derivation is A里AB.

Unfortunately, this pattern was only displayed as an example, but not explained.
This pattern, like you mentioned, seems to be referred to as &quot;A里AB&quot;式 in Chinese.
A quick search came up with the following list of words:
糊里糊涂hū lǐ hū tú
怪里怪气guài lǐ guài qì
流里流气liú lǐ liú qì
傻里傻气shǎ lǐ shǎ qì
土里土气tǔ lǐ tǔ qì
慌里慌张huāng lǐ huāng zhāng
妖里妖气yāo lǐ yāo qì
彻里彻外chè lǐ chè wài
胡里胡涂hú lǐ hú tú
没里没外méi lǐ méi wài
秀里秀气xiù lǐ xiù qì
歇里歇松xiē lǐ xiē sōng
小里小气xiǎo lǐ xiǎo qì
打里打外dǎ lǐ dǎ wài
蹀里蹀斜dié lǐ dié xié
疙里疙瘩gē lǐ gē dā
古里古怪gǔ lǐ gǔ guài
鬼里鬼气guǐ lǐ guǐ qì
火里火发huǒ lǐ huǒ fā
楞里楞气léng lǐ léng qì
啰里啰唆luō lǐ luō suō
蒙里蒙懂méng lǐ měng dǒng
噗里噗通pū lǐ pū tōng
痞里痞气pǐ lǐ pǐ qì

There also seems to be a couple of studies about this speech pattern:
浅谈“A里AB式”
现代汉语“A里AB”格式的研究
but that's all a bit pedantic for our needs...(although you can be sure it is a set pattern)
It seems like you have already explained it pretty clearly as well:

According to my book, there is a pattern for building further adjectives from adjectives. If the original adjective is AB (two different characters), its derivation is A里AB.


as for the meaning:

...意义并未改变。例如 ： 马虎， 意思为做事不认真 。变为　
“ Ａ里 Ａ Ｂ式 ” 马里 马 虎 ， 思 同样 为 做 事 不 认 真....浅谈“A里AB式”

The meaning does not change. For example: 马虎 and 马里马虎 both mean 做事不认真.
AB and A里AB mean the same - with a stronger sound/meaning on the A里AB than the simple AB pattern.