The Meaning of Life, the Universe, and Everything.
(Sorry for my English, I helped with a translator).
Since I knew Minecraft is a game I like a lot and I am very meticulous creations both in architecture, and the accuracy of circuits restone very complicated.
However, until Minecraft 1.2.5, I used the Singleplayer Commands mod made by a famous modder SIMO (unless I'm wrong), and I used the commands (mod) to eg noclip (/noclip to cross the block as a ghost, transparency and see when I'm inside blocks), which allowed myself to correct errors or make very careful constructions without destroying what bothers me.
I used other commands that was very interesting as /reach with a number to set the length of my arm to reach more (or less) of blocks from my position to change them.
There had other commands like /SetSpeed the liberty of which set the speed of the player is very useful to move or fly (or walk or noclip Fly in creating one point to another without losing time.
Since the 1.3 update all these commands are impossible and SIMO (the modder) just to put them back in service and the fans of this mod really starting to get impatient. Other mods we tried to integrate the noclip but without success.
So I make a suggestion to you, the Mojang team in charge of developing Minecraft, since you built orders SSP and SMP, add an equivalent of these commands and others resulting from this mod (and provided it does not interfere or SIMO thank for his mod), it permettrais creators to greatly facilitate the task in their creations.
For some creations of great importance, I'm stuck in Minecraft 1.2.5 because of orders /noclip, /reach, /SetSpeed and /bind command (to assign a hotkey to a command), and I was obliged to Pause my tutorials that I used to put on Youtube for example, to the chagrin of my subscribers.
Additional suggestion: Would it be possible, if you go to my request, these additions to the "Command block"?
Well, if you read this message, you will help to meet many players in their Minecraft creations, and thank you very much for giving me the pleasure to play and create with your game
PS: I use many commands since I played GMOD or "source" games Valve and allow a lot to commands from their console.