I know you explained your reasons to me in another thread. That doesn't mean you're right.
Can you explain what the difference is between doing a direct disk->disk clone and doing an intermediate image save to another disk? What makes you think it is safer? In both methods the identical thing is happening, data is read from the original drive and written to a 2nd drive. Think about it, THERE IS NO DIFFERENCE IN REGARDS TO THE SAFETY OF THE DATA.
I worked in IBM's disk drive business for 20 years and never once heard of a situation where copying data from a disk somehow corrupted the data on the original disk. If copying directly to the clone drive would effect the data, so would copying to the intermediate drive.
Depending on the disk imaging software, different things can happen.
In my case, I'll be as detailed as I can for you since you don't remember from the other thread.
My friend bought a new SSD. He wanted his drive cloned to the new SSD. I shrunk the partitions with GParted so they would fit on the new SSD like he wanted them to be, and then I loaded up Clonezilla. I started the direct disk-to-disk copy because i figured "hey, it's just a direct disk-to-disk clone, so it should be fine." It asked if I wanted to make the new drive bootable as well. I answered yes to this prompt, and continued with it. It was copying fine, and somewhere during the copy, something went wrong (could have been a bad sector and I forgot to add the "ignore bad sectors" option, could have been something else - not sure since I wasn't watching it at the time). So I figured, "well I'll try again, but let me make sure I can still boot into the original drive." Tried to boot - failed. No OS detected. Tried to repair the bootloader - couldn't do it. Tried rebuilding the bootloader / bootsector from scratch using a Win7 disc. No dice. Tried making the old partition active in diskpart - still wouldn't work. After several hours of attempting to get it to work (couuldn't reinstall fresh because he didn't have install discs to some software he had on there anymore), I finally managed to get it to boot again (can't even remember how I did it). Then, there were a bunch of registry settings that got ****ed up somehow, and the program files path and several other system paths were pointing to the wrong drive letter, so I had to manually change those. Finally got it fixed and working fine after about 6 - 8+ hours of working on it continuously. Then we decided to try cloning to the SSD again, this time making an image. So, created the image onto an external of his, and then applied the image from the external to the SSD. Rebooted, and guess what? Worked fine and he was happy as a clam.
So, yes, theoretically doing a disk-to-disk is just fine. Hell, I used to to disk-to-disk when I had to clone drives. BUT, it just takes that 1 time that something goes wrong, where I had to spend that much time fixing the issue that could have been avoided by simply doing Disk-Image-Disk.
So, there you have it. May not be "safer for the data" in a data integrity sense, but it's safer in a "you won't **** up your drive and have to spend hours recovering data" sense.
Also, you're misinterpreting what I'm saying. I'm NOT saying it's CORRUPTING the data. I'm saying it's safer from the standpoint of TIME and the possibility of something going wrong, such as what happened to me. Yes, it was probably a fluke that something wrong happened. BUT, that's enough for me to do it a safer way.
So there you go, you now have a "first" for your 20 years about disk imaging.
And just because you do disk-to-disk, doesn't mean that's right either. You can use your technique, and I'll use mine. Doesn't matter to me - I'm just giving my opinion and experiences to people that ask for help in regards to how they should do an image of a HDD, and I've had many many people agree with me that doing disk-image-disk is "safer".