Am I shifting/using the clutch too often?

[DeDCrispix]

Pretend you're on the freeway...doing 65-70. Now you're in 6th (manual of coures) and you want to give her the beans, so you drop down to 4th. Now when I do this, I clutch in, go to neutral, clutch out, rev, clutch in, 4th gear, clutch out. Doesn't take me more than .5 seconds but this is so unnecessary right? (I came from a beater with a manual that shifted more smoothly shifting like this). Carried this "bad habit" when going to a 98 Mustang GT...and still do it in my Z.

Pulled this from wiki 'double clutching'.

"The purpose of the double-clutch technique is to aid in matching the rotational speed of the input shaft being driven by the engine to the rotational speed of the gear the driver wishes to select (directly connected to rotating wheels). When the speeds are matched, the gear will engage smoothly and no clutch is required. If the speeds are not matched, the dog teeth on the collar will "clash" or grate as they attempt to fit into the holes on the desired gear. A modern synchromesh gearbox accomplishes this synchronization more efficiently. However, when the engine speed is significantly different from the transmission speed, the desired gear can often not be engaged even in a fully synchronized gearbox. An example is trying to shift into a gear while travelling outside the gear's speed or directional range, such as accidentally into 1st from near the top of 2nd, or intentionally from reverse to a forward gear whilst still moving at speed.

Double clutching, although time consuming, eases gear selection when an extended delay or variance exists between engine and transmission speeds."

So...in theory...good. In practice, waste of time?