so what yer saying is...
if there is no volts on the wee wire it wint work
CORRECT!
try taking the warning bulb out and see what happens
It may stop working, but not always. Some are wired a little differently. Not all depend on the bulb as part of the field circuit.
if there is no volts on the wee wire it wint work
CORRECT!
so how does it blow the **** outta it self when disconnected but injun running.
Because it may self-excite (easy girls ...) as you said earlier, even though there is no voltage on the wee wire, and the now working alternator system then "sees" no voltage at all, and so it sends MAXIMUM possible power to the wee wire. Now, remember, the wee wire is connected direct to the big wire if the IGN is ON. So, in effect, it sends all the power it makes straight to the wee wire, because there is nowhere else for it to go if there isn't a battery connected. The thing then runs out of control in a viscious circle that leads to self-destruction in no time flat.
Remember what boys were told in the olden days ... self-excitation will lead to self-destruction!
CharlesY