I'll speak up for the other school of thought on using or not using the adapter for cleaning;
A cable release is the alternative method, locking type, naturally. Manual exposure, shutter speed set to Bulb, and lock the shutter open. If the shutter closes while you've got your finger in there, you're out about 600 dollars. Just want to mention what you're dealing with here....If you've bought the adapter and are using it while there's a power fluctuation at your house, you're hosed. Using my method, there is no way in hell the lock is going to allow the shutter to close, go ahead and push on the end of the cable and try it.