aeration process

[PRECISION LC]

what is the process to aerate, i know about the single and double pass. but dragging smooth, i'm not sure what this is. and as far as over seeding and dethatching im ok with , but just wondering when the best times to do this is, and what is the process you take to get the best results.
thanks
kyle

[MacLawnCo]

Not to be snooty, but do a search. i think there are more than a dozen pages with mention of aeration.