Yeah, well my car hasn't been modified much further so there hasn't been the impetus, and when i looked at it properly you really need an emulator to do the job right.
IMHO it's just not a feasible process to:
Dyno -> Change Tune -> Erase Chip* -> Burn Chip --\
^ |
| |
\------------ Repeat til done <-------------------/
*You really need a special eraser for this, you can leave em in the sun but it's unreliable, or you can keep using freshies at ~$10 a pop.
Which is why, from what i can gather, Sam originally had a generic tune and made the odd tweak here and there.
Once you factor in the equipment costs for an individual it's more economical to go the PowerFC route.
Edit: And you'll STILL need Dyno time, and someone to tune it (unless you're confident with it yourself) who will be unfamiliar with the process, which despite it's benefits is why it'll always be a bit of specialty to certain tuners.