nee. impedanciu by si dosiahol aj bez krutenia (viz ztare historicke antenne kabely ploche). Ale to krutenie je extra vymyslene na eliminaciu el.mag.poli v diferencialnom signale a je to aj fyzikalne nejak odvpdene a vypocitane a dokazane ci co :)
P.S. Velmi pekne je to popisane tu a hostoricky sa najprv nekrutilo, ale potom niekto prisiel na to ze krutenim sa da lepsie eliminovat crosstalk a el.mag rusenie.
http://en.wikipedia.org/wiki/Twisted_pair

One pair can induce crosstalk in another and it is additive along the length of the cable. Twisting the pairs counters this effect as on each half twist the wire nearest to the noise-source is exchanged.