Tony,
The big problem with what you propose it that it's too easy for something to go wrong.
Here's a few sentences I found on this subject. I'm sure if you search you can find much more: (bold is mine)
WARNING: Improper connections to a building's electrical system can allow the generators electrical current backfeed into the utility lines. Backfed power may electrocute utility workers or other individuals who may contact the lines during a power outage. Consult with the utility company or a qualified electrician.
Improper connections to a building's electrical system can allow electrical current from the utility company to backfeed into the generator when power is restored. This utility backfed power may cause the generator to explode, burn or cause fires in the building's electical system.
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