BZZZZZZZZZZZZZZZZZZZZZZZT!
Shocking, I tell you......absolutely shocking!
Only seven state still allow electrocution as an option for the death penalty.
Safely for you or for the linemen?
If you do end up making a "suicide cord" to backfeed your house, I would recommend not actually making it until needed, and then dismantling it when finished using it.
Otherwise, you have an extension cord with 2 male ends, which if left lying around, may end up killing some unsuspecting kid or unknowledgeable adult.
^^^^This, or, connect the 'house side' of the suicide cord, FIRST, then connect to generator after starting it.
if you don't open main breaker you can feed 220v through your service and back to transformer and the transformer will take the 220v and produce up to 7,620v. some linemen take things for grated and if he is assuming the equipment is de-engized he could make unprotected contact with high voltage.