Larry, you have a real pair of brass ones to sit there and say that your opinions are fact are mine are misguided. I am looking at the Helm factory service manual provided to dealers for the correct service and repair of GM vehicles. I am looking at page 7-325 that talks about fluid replacement for the 4L60E. in summary it says to drop the pan, replace the filter, install the pan, and fill with fluid to the correct level. Disconnecting lines is only referenced with regard to checking line pressure, checking cooler flow, etc. the same procedure is givenj on page 7-575 for the 4L80E.
granted my manual is for 2001 vehicles and may not be applicable to the OPs 2010 Silverado, but certainly no less appliacble than your service knowledge of your Ford vehicle.
as a reminder, this is a public forum and for you to indict my opinions has dangerously misleading while canonizing yours as unimpeachably correct is the height of arrogance and ridiculousness. You must not have many friends.