Editing from Boot Drive?? Apple says yes.

Question

In dealing with Final Cut Pro X's Pro Apps team I was told something by TWO different Pro Apps people I find troubling. They each stated that you should ALWAYS edit fotage (meaning keep your projects and events) on the INTERNAL BOOT DRIVE. This would provide the best performance and is how FCP X is designed to work. I am not kidding or misunderstanding. I even clarified this to make sure we are clear between a second internal drive and the actual boot drive handling the OS. I was told "in the new 64 bit architecture, FCP X is designed to edit from the same drive the OS is on, the only issue is storage space". It was then reiterated that this is the best way to use FCP X. I even explained that if I was using some kind of consumer level format, I could see doing this, and explained I shoot in AVCCAM 1080p. Apparently what format you use does not matter either, it is designed to handle anything I was assured. So, my 3  year old MacBook Pro will edit RAW 4K footage from the boot drive? I am amazed!
  Sadly, the solution provided to my FCP X issue is "wipe the hard drive completely and start over." This after paying $99.00 for the Pro Apps support and talking to no less than 8 people. I am certain none of the Pro Apps folks I talked to really understood what I am even dealing with.
  Their Pro Care is not what it used to be, although the person who told me this said he has been doing this for 7 years. Unbelievable.
Comments?

Answer 1

I wish I could get to one of those engineers, I had an issue when FCP X first came out and eventually talked to one over the phone. All I dealt with back then seemed on their game. I just thought Apple was better than that.
I have another genius bar appt. today. Should I let them do the long hardware test? They say it could be a day or two and is much more extensive.
I would likely try to buy a new iMac before paying hundreds for a better card and trying to install myself. It seems they would  not do it at the Apple store, only replace the same card. 
here is the full system report on the ram, when I paid for the upgrade, they put two 2GB cards in instead of one 4GB, see anything of interest here?: 
One card slot says:  NVIDIA GeForce 9600M GT
the other:   NVIDIA GeForce 9400M
NVIDIA GeForce 9400M:
  Chipset Model:          NVIDIA GeForce 9400M
  Type:          GPU
  Bus:          PCI
  VRAM (Total):          256 MB
  Vendor:          NVIDIA (0x10de)
  Device ID:          0x0863
  Revision ID:          0x00b1
  ROM Revision:          3448
  gMux Version:          1.8.8
NVIDIA GeForce 9600M GT:
  Chipset Model:          NVIDIA GeForce 9600M GT
  Type:          GPU
  Bus:          PCIe
  PCIe Lane Width:          x16
  VRAM (Total):          512 MB
  Vendor:          NVIDIA (0x10de)
  Device ID:          0x0647
  Revision ID:          0x00a1
  ROM Revision:          3448
  gMux Version:          1.8.8
  Displays:
Color LCD:
  Display Type:          LCD
  Resolution:          1440 x 900
  Pixel Depth:          32-Bit Color (ARGB8888)
  Main Display:          Yes
  Mirror:          Off
  Online:          Yes
  Built-In:          Yes