Hello,
I'm not sure the inside processing of command "execute", I think the reason for "Why does the jump command with an invalid address works as well?" is your image start from 0x00000, so no matter the address is , it always start up from 0x0000, it can work well.
If image start from other address, for example, in mcu, a secondary bootloader +APP module, APP
start from 0x1000, then the <address> should the exactly data as User's Guide said.
Or image is in RAM, also <address> need read from first 8 bytes.
BR
Alice