Not necessarily on the week and a half part. There are those that don't use secondary at all, either not believing a change in taste occurs by sitting on the yeast or enjoying it. There are also those that leave it in primary for long period (or forget sometimes
. And there are also those that transfer to secondary as soon as it reaches below 1.020, I try to aim for this personally. This way the bulk of fermentation is over, but the last bit will provide more than enough c02 to blanket secondary and ward off oxygenation. This last option's schedule is based more on the quality/speed of fermentation than anything, as it can take a day or two or a week or two.