Originally Posted by merlinextraligh

No. For a couple of reason, you end up slower on a ride with half tailwind and half headwind, than a ride with no wind.

First, you spend more time into the headwind, and thus lose more time than you gain going into the headwind. (This is the reason you push harder on the headwind leg of a TT, and recover on the downwind, because more time is at stake on the headwind leg).

Second, most winds are effective headwinds. Only winds coming from a small portion of angles directly behind you help. At most riding speeds and wind speeds, cross winds are headwinds.