cddoes not actually change the working disk; it only changes the working directory for this drive. That's why he crashed so much.
An example might help:
C:\users\david>cd D:\some\path
C:\users\david>
Please note that the drive has not changed.
C:\users\david>D:
D:\some\path>
Now that D: is the "working disk", the working directory changes to what you specified earlier.
, cd /d . [UPDATE: , , /d :( - sorry]
, - "" - COMMAND.COM(, , /d), script .cmd, , COMMAND.COM.
IMHO pushd, cd /d, , ( popd). pushd UNC- (\\server\share), Windows . ( , Win 7 Pro, , / Home.)