Thank god... Lascelles is at the core of all the problems. He always wants to sit on the edge of our box and naturally wants to drop off, plus he's always being dragged about which creates huge problems. He'll make a few good tackles and most fans don't understand the game so they'll have convinced themselves those tackles make him a great player, but unfortunately he is not.
I don't think it's necessarily a rule, it's just always built into the contract that a loan player can't play against their parent club. Except when dumbasses forget to do this, ie allowing Lua Lua to play for Portsmouth against us when we loaned him to them, and of course scoring for them against us.