Alligning tiles on your gridline

Do you center your gridline or do you line it up with the edge of the tile? I always center my gridline but is there an advantage of lining up the tile right on the edge of a gridline? When doing a layout, I always count the tile plus the grout joint and center the grout joint. For instance, if my tile is 11 and 3/4, and my grout joint is 1/4, I'll have my gridlines 1/8 inch on either side of the tile (this is of course if my gridline covered only 1 width of tile). How do you guys do it?
Thanks

Isn't there a lot of guess work in that procedure? Never heard of anyone doing it that way.

Bring the edge of the tile to the mark and be done with it.

When setting the layout add the desired grout width to the tile dimension multiply by two and there's your grid dimension to lay down.

On pg 137 Michael Byrnes "Setting Ceramic Tile" he talks about setting the tiles. He says "I laid down all the tiles in one square and then began aligning them by butting the first vertical row snugly against a long straightedge, positioned half the width of a grout joint from the layout line".

Pretty sure he's talking about centering the lay-out lines, otherwise he would lay the straightedge right on the line. Maybe all these years I've been doing it wrong but could you tell me which 2 lines of your 4 lined grid you butt the tile against?
Thanks

Is that the Byrnes book published in 1995? Throw that thing away.

If you are using 12 to 13 inch tile you can be more efficient if your grid pattern includes two tiles and two grout joints each way. That's reachable by the average person and the math is do-able. Once you snap-down your layout throughout the entire room there is no need to use a straightedge to begin with but if you must - you must. Lay down your lines so that as you back away from the freshly set tiles you are looking at the layout line that the tile edge nearest represents. Once you have your layout. Spread your thinset within the lines of the grid box you have created that represents four tiles.

Key the thinset into the substrate first with the flat side of the trowel, then turn the trowel over and comb the thinset in one direction only. Get as close to all four lines as is practical with the thinset. Usually a left to right or right to left combing in front of you is the most comfortable. Once the combing of the thinset is complete, plop a tile in the thinset near the layout line closest to you that you have just spread with thinset. Move that tile away from you (and the line) slightly to cave the ridges, then move the tile back towards yourself to position the tile and continue to "seat" it into the thinset. At this point the tile should be suitably nested into the thinset. Do it again to your left or right with the next tile. Then again above the first two tiles. Each time properly nesting the tiles into their final resting place. Check to be sure that the tiles close to you stay with the layout line and the tiles away from you maintain the proper spacing.

That's all there is to it.

In the time it has taken me to type this I could have had a dozen tiles in place. That's how quick it goes.

Byrnes is known to be anal about things so take what he has written with a grain of salt. He's not the almighty he would have you believe he is.

You won't need a straightedge and you certainly don't want to use spacers. Spacers will only throw you off course. Stay with your layout no matter what. When you find you have a weird tile, tweak it slightly. Once the grout goes in you won't notice an occaisional slight variance.