It might still be 1:1 when you think about it because their wording was very vague and "more efficient" could simply be referring to the fact that Pet: Accuracy gear tends to come with a larger number than Summoning skill gear, so for example it would be more efficient to equip one ring with Pet: Accuracy 30 than 2 rings with Summoning skill +15 (these are just example numbers/example equipment)
Of course a lot of stuff you would bloodpact in already has summoning skill on it so it doesn't hurt to squeeze it in where you can as long as you don't make huge sacrifices for it
I doubt the conversion rate is lower than 0.9 = 1, from what I've experienced.
XI Wiki


