That's a great question. It's something I should've covered in the Instructable. There are two reasons:
1. My controller has separate outputs for Heat and Cold and from what I'd read it sounded like there are separate windings in the blower motor (2 different speeds I guess). Later on, this will allow me to install a second relay that will be energized by the Cold circuit, that way, my fan will kick in when the AC is on as well.
2. Liability, if my fan is totally separated from the control board via a relay, then I don't have to worry about it damaging the control board if something happens on the fan side.

Also, the relay option will allow other people to control fans that are not 115V, say 24V. Obviously they will have to use a separate transformer or use the one that's already in the furnace but from a control point of view, using the relay keeps things segregated and safe.

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“There were some inconsistencies with voting that didn’t make sense, so we felt that a re-vote was needed to get a good gage on everyone’s opinion. We wanted everyone to vote. The crowning should reflect who the student body believes best represents the cardinal student, and after the re-vote, we achieved that. We will continue voting with our new procedure. With having every class vote we get the whole student body's opinion on a good representative for our school because essentially that’s what the vote is all about; the students’ idea of who best represents DT,” said Lavaley.