Widely unknown is the fact that the collector is comprised of such a (parasitic) diode as well (same direction like emitter) but will never be drawn in schematics. Therefore even electronic engineers seem to miss this fact.
Having said this we are able to control the transistor "valve" by collector as well. We can operate a transistor by interchanging emitter and collector. The amplification factor will be very low but the losses in this transistor might be considerably lower. In old times analog sages used this parasitic effect to do some miracles in electronics. BTW: Electronic components own a lot of genuine but not documented "parasitic" functions and as far I know John Bedini was on master of making use of them.

To be continued in next post ....