???
Is this supposed to be another "Oden's Haki" argument?
What do you mean "very loosely around his body"?
Honestly, I don't see that case at all.
The thing is, that amount of seastone isn't nearly enough to restrain Loki's power that much which he has stated on Redon's summary. The giants (or Shanks??) made sure to put as much seastone chains and cuffs on Loki's body as possible.