Sure, why not. It will still be beer.
Corn sugar brings no flavor to the party. LGS might bring some subtle flavors of its own.
My guess is the it would be roughly like the substation ratio of DMW to LME which is, I if I recall now that DME ~44 ppg and LME is ~36 ppg. If your off a few gravity points it's really not a problem.
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