I can see why people think Bergvall is decent, he does a good show of being a decent footballer, but right now there's no intelligence to his play, he just runs around kicking people and looking busy when he'd be much better off calming the fuck down and doing his job. Spurs were in a relegation battle (and just out6side it last year) largely because their central defence and midfield are tactically inept, dragging the midfield around to create gaps is ridiculously easy and he's probably the worst for it.
I'd want to be very certain that he's capable of learning to do his job properly before even taking him on loan let alone throwing any real money at them.