I don't know what you guys are talking about with that being a big grain bill. Belgian blond is to be between 6 and 7.5% abv.
I only meant to say that at a conservative 78% efficiency, 12 lbs of Pilsner malt and 3/4 lb of table sugar would yield a very high PBG. After boiling for an hour you'd likely be >1.090 OG. That struck me as uncharacteristic of the style.
You'd be looking at a large ABV beer even with modest attenuation. Given the nature of good liquid Belgian strains when sugar is involved, >80% attenuation is not unlikely. If that were the case, you'd very likely be approaching ~9-10% ABV.
To each their own. It would be a tasty beer regardless. I am of course assuming a 5 gallon batch.