I'm wondering if there's a command I've not found or a shortcut I'm supposed to already know about... Is there a way to place more than 12 blocks in a row? I'm trying to fathom how some of these creators have made landing pads that appear to be a hundred blocks in all directions. I just labored to make a landing pad for the CV I spawned in last night and it took FOREVER solely because I was limited to laying blocks in 12 block lengths. Also is there not an X/Y type of block placement for floors, allowing placement of say 50 blocks by making a 10 x 5 grid, assuming the ground is flat enough for it?
Creative mode and survival mode are different. In survival you can only place lengths of something like 11 or 12 blocks (can't remember exact amounts), but in creative mode you can place much larger amounts of blocks at once. Creative mode also has the copy/paste functions which you can use to build large and complex structures much faster.
Pretty sure it has something to do with Structural Integrity, since 12 blocks is, if I recall, the break-length for a single unsupported span. In creative mode, I don't believe SI is applied, but I don't do a lot in Creative, and nearly all my constructing is done in space.