Low Final Gravity

So I just bottled a Belgian Blonde/Pale
Slightly tweaked from Jamil's recipe from Both...

My Final gravity is 1.002~1.003

Which is ridiculously low in my mind? Is it?
I mashed at 151 by the end of the mash it was 149

So did I mash too low? I still would think it would be higher.
I tasted it out of the hydrometer tube and it seemed like it will be ok but I just thought that was too low??

The OG was 1.063

I used the Belgian Trappist yeast from White labs

Fermentation was 68~70

yeah I know that the low temps will make it more fermentable, but I didn't think it would be this low for starting at 151? I was aiming for 152 and missed it by a degree. It lowered to about 149 but that wasn't til late into the mash.

That is like a 95% attenuation. Seeing you have 142 posts I am sorry to ask this, but are you sure you read the hydrometer correctly? That seems extremely low for an FG. I have to work that yeast hard to get in the 80-85% attenuation (starter, higher ferm temp, etc).

I Know that is Crazy attenuation, LOL! That is why I posted this, I have never seen anything like it in the years I have brewed. I used 2 cups of normal cane sugar, added to the boil.
I always make a nice big starter, but I don't think that would make it that low of an FG...
I used the hydrometer like always it was around 68F when I too the reading for FG
and about 80 when I took the reading for OG. Which I know changes it a bit but not that much??

OG in my notes says it was 1.063...I don't think it was a 5, but even if it went from 1.053 to 1.003 that would be a lot?

Well I found out the problem. When I tasted it first couple times there were no noticeable problems....but I tried 2 this week and ettbeer is right it got something nasty like wild yeast or bacteria in it that took it down to 1.002. It tastes awful!

Well my first ruined beer in over 6 months

Now the question is, dump or see if it sours to a decent taste?

Leave it alone. Many of us strive for infected beers... what does awful mean? Tart? Sweaty? Grassy?