Tmemphis wrote:
Your missing the point and are blinded to reality
No, and please drop the attitude. Let's limit this to facts, please.
What you are suggesting is fine if you know your way around technology
No.
Kindly recall the original question in this thread: how to do a "clean install" to upgrade from Snow Leopard to Lion. The answer from two of us in this thread (and many others in other threads here), is: "you don't need to."
Upgrading is quite simple; basically just follow the prompts.
Doing a "clean install" requires you to "know your way around technology" far more: if you don't already have backups, make some; erase everything; install OSX; restore or reinstall everything else. That last part usually involves a number of different steps, is tedious, error-prone, and time-consuming.
Your assuming every one is an expert and use Time machine.
No, not for the original question of upgrading OSX.
Most of the other scenarios you raise require some sort of backups. If you replace your internal HD, for example, you need some way to get your data onto the new disk. The only way to do that is to back it up first.
Either cloning or Time Machine (or, preferably both), are quite easy. For Time Machine, it's basically just connect a HD and let Time Machine configure itself when it asks. See the Time Machine Tutorial, and perhaps browse Time Machine - Frequently Asked Questions for details.
As for your response to 2 , the Apple Gennius formated my HDD and put Snow leopard back on when they couldn't get it going iether...
Without more information, there's no way we can address that, and again it's extraneous to the original question in this thread. We don't know if there are hardware and/or software problems, or perhaps a misunderstanding of some sort.
If this is still a problem, here's what I'd recommend:
Run Verify Disk, per #6 in Using Disk Utility.
Then run Repair Disk Permissions, per #5 there.
If neither shows any problems, upgrade to Lion via the AppStore or purchased USB stick.
If that doesn't work, and you want help sorting it out, post all the relevant details in a new thread (without the attitude).