I have been looking for a cheaper version of Rowan's Calmer to make myself a jumper. i like the debbie bliss cashmerino aran. both are double knits, but when i did a tension square, the debbie bliss was 13 cm, to rowan's 10 cm. does that mean that i can use it, but knit a smaller size to get the right finish? if so - how much smaller? it seems quite a big difference to me, but the pattern is a very loose rib, so may not come out quite so much bigger? please help!