Can Erap run again as President?

We’ve been hearing a lot about presidentiables for the 2010 elections in the news lately. Just recently a Pulse Asia Survey showed was released and revealed the topnotchers as de Castro 19%, Senator Francis Escudero 17%, former President Joseph Estrada 16%, and Senator Manuel Villar Jr. 15%. Wait. Former President Estrada? Can he really run again?
The pertinent provision of the Constitution says: “The President shall not be eligible for any reelection. No person who has succeeded as President and has served as such for more than four years shall be qualified for election to the same office at any time.”
Now, is the ban absolute? I have read materials regarding the issue and found that if we are to look at the meaning of reelection, then we may find otherwise. Neal Cruz of The Philippine Daily Inquirer says that some believe that “Reelection refers to an official running for the same position during his incumbency.” So since former President Estrada is not our incumbent president, the ban does not apply.
The Supreme Court has not decided on the issue whether former presidents in general may run again for presidency so if Estrada decides to run again there is no legal impediment against it. The argument on the definition of reelection strongly supports the claim that it is constitutional.
As for the executive clemency granted by Gloria Macpagal Arroyo to Estrada after his conviction for plunder by the Sandiganbayan that says in its preamble that he is no longer to seek any elective position or office, Chief Justice Artemio Panganiban, in a Jan. 19, 1999 decision held that the preamble or the whereas clauses of a law or any presidential issuance such as Arroyo’s executive clemency is “really not an integral part of a law … and cannot be the origin of rights and obligations … and can neither expand nor restrict the operation, much less prevail over its text”. Clearly, even this does not and cannot bar Estrada for running for any office, including the presidency for that matter.
So, can Estrada run again for President? Yes, absolutely.