"If he says you have relatively superior IVs overall, it means the sum of all your IVs is between 121 and 150. This means they could all be 21 across the board, or have abysmal IVs in some places but perfect IVs in others. He will tell you afterward what your highest IVs are, and unless he mentions that stat "can't be beat", you do not have a perfect 31 IV. "Outstanding" stats is the sum from 151 - 186, which is max 31 across the board. I think he will also tell you if you have a 0 IV stat.
For example, the Pokemon has "outstanding" stats. He will then mention HP, Attack, Defense, and Speed as "can't be beat." Then he will say something along the lines of "how can you survive with that Sp Def stat?"
Then you know your IVs are 31/31/31/27-31/0/31. You can infer the special attack because you know your Pokemon has "outstanding" IVs, so the sum has to be at least 151."
