WLP 500 attenuation

Hey guys I think I am going to start brewing belgian style beers this winter. I have a question concerning attenuation.

Say you have two identical grain bills and make two identical worts.
ie:10 lbs US2row and 2 lbs crystal 60 resulting in a SG of 1.055

If you used 2 different yeast:
WLP500 Trappist; Attenuation 75-80%
WLP001 Cal Ale; Attenuation 73-80%

Would both of these beers result in the same FG or would the cal ale finish lower as this is an american style grain bill?

In my experience, in a perfect world, they would end up with the same FG. But your FG is dependent on many factors other than just the OG of your wort, such as the health of the yeast at hand, temperature fluctuations, etc...

Yes, agreed that in the real world they would never come out the same. I was thinking more of a perfect world scenario.