@tbavprof....i have taken the following from the CAR released by ATO/CAAP on 23June2008.
taken from section
2.3.3.5 MULTI-CREW PILOT LICENSE (MPL)
2.3.3.5.2 REQUIREMENTS
(g)
Privileges. Subject to compliance with the requirements specified in this Part, the
privileges of the holder of an MPL shall be:
(1) (i) to exercise all the privileges of the holder of a private pilot license in the
appropriate airplane category provided the requirements have been met;
(ii) to exercise the privileges of the instrument rating in a multi-crew operation;
and
(iii) To act as co-pilot in an airplane required to be operated with a co-pilot.
(2) Before exercising the privileges of the instrument rating in a single pilot operation,
the license holder shall have demonstrated an ability to act as pilot-in-command in
a single pilot operation exercised solely by reference to instruments.
(3) Before exercising the privileges of a commercial pilot license in a single pilot
operation, the license holder shall have:
(i) completed 70 hours, either as pilot-in-command, or made up by not less than
10 hours as pilot-in-command and the necessary additional flight time as pilotin-
command under supervision;
(ii) meet the requirements for the commercial pilot license.
(3) Act as second-in-command/co-pilot in commercial air transportation in airplanes
required to be operated with a co-pilot by the type certificate of the aircraft or the
regulations under which the aircraft will be operated; and
(4) When the holder of an airline transport pilot license in the airplane category has
only previously held a MPL, the privileges of the license shall be limited to multicrew
operations unless the holder has met the requirements established. Any
limitation of privileges shall be endorsed on the license.
As made clear by point (4) an MPL holder can directly upgrade to an ATP.
Also from a purely logical point of view...why on earth would an airline invest on a life long copilot? 
That too 50+ of them?
Agreed that when ICAO approved of MPL in Nov 2006, it was not as if all the contracting states had integrated MPL into their systems! The implementation part was left to the contracting states...and it does take time for each state to implement the new type of license...which also happens to the first new type of license since WW II!
Before one puts something down totally (even before giving it a chance)just because the current gudelines do not have any provision, please atleast acknowledge that something different is being attempted...and it took ICAO 5 years to arrive at MPL. It will take some more time for the contracting states to fully implement it.
Way back in 2006 when the debate on MPL was going on in the Indian internet forums...the primary detractors for MPL turned out to be some well known FTO owners in India! Surprisingly some of the people in favour of MPL were the retired TRIs/TREs!