Yeah thats a load of old bollocks, there are no capacitors inside the ecu that could retain data for that long, nor is there any battery backup.
The data on the 06, just like the 05 is stored on a flash memory which can retain the data without power for around 20 years , there are two ways of clearing the memory, one using a reset tool (learnreset) which you can get off my site and use a drewtech mongoose/cardaq/scandaq/cardaq plus, or method two damage the CRC (checksum) of the data block/erase it all together.
In order to damage the CRC you must turn off the power to the ecu when its saving the changes internally, this is done by running the car for a while, then removing the key and before you hear the click of the relays, remove all power, next time the ecu starts up it'll see the damaged data and reset it.
the latter method is tricky, but i do it all the time on my bench ecu its probably a good way of damaging the ecu too, so I wouldn't do it.
if you're unsure it worked, make it set a code ( fuel cap off is easy ) and the light is on, and an OBD II tools reports the code after a switch off/on cycle, then do the reset procedure and the code reader no longer reads the code its been reset correctly.
be aware not all codes will light the MIL/CEL after a restart, so a lot of people mistakenly see this as the ecu being reset, when in fact it isn't, you should still see a code on a proper OBD II reader.
you could potentially damage the flash memory by power spiking the ecu and causing it to reset or boot up incorrectly, but this isn't wise especially on an 06 ECU as they are very easy to damage, also you don't want to try to erase the flash chip on an 05 since it stores the learn in the same flash chip the program is stored, the 06 has two seperate areas of flashable memory for learnt data and program so its possible to kill it too, but a bit harder, if you manage to wipe out the chip only a specialised programmer can resurrect it, not any of the lotus tech tools.