yup, and Andreas' book is great!
There are lots of OpCodes not used, or their combinations creates transactions, which are not forwarded.
I think this is a protection of the network, to avoid loops in scripts and similiar. But the experts need to confirm.
When trying to play with scripts, there is lot of history here, maybe a bit longer ago, but search the forum (maybe the keywords like "OpCode" and "bitcoin contracts").
And when you have an idea, try it on testnet first, then go to live net. I had a lot of help here:
http://bitcoin-script-debugger.visvirial.com/p.s.:
found the reference here in the forum:
https://bitcointalk.org/index.php?topic=1840303.0