Cedar Rapids Brewing Society

So, I had a Blonde Fatale, and am thinking about trying to make a 'sneaky' strong ale.

This is going to have a portion of the fermentables being simple sugars. I am thinking about taking table sugar and add enough water to make this a syrup. And then heat gently to invert the sugar (similar to candi syrup but without caramelizing)

Is adding 15 to 20% of the fermentables as simple sugar too much? And since the sugar should ferment out completely I should not account for it when planning how much bitterness to add?

The IBU is a function of the wort gravity, not the fermentables. IBU calculations consider boil time and gravity to estimate the IBU's extracted into the wort. If you are planning on "feeding" the sugar syrup into the wort after fermentation has started then you may only need to calculate the IBUs based on your wort gravity but I still think it is based on total starting gravity. Correct me if I'm wrong, someone.

I don't think 20% is too much simple sugar. Most belgian triples or golden strong ales use quite a bit of sugar, 3lbs in a 5gal batch if I'm remembering right.

Also as a side note, heating table sugar in plain water does not make invert sugar. You have to add a small amount of acid, such as citric acid or lemon juice. You can look up a recipe but I don't think you'll need invert syrup. Just heat the sugar water to boiling to sanitize and dump it in!