Gurmukho, To comence with a Sikh is NEVER baptised.The questions of baptism NEVER arises in Sikhism nor should ever arise.I dont know how you have arrived at such a conclusion that a Sikh is ever baptised. The claim "It actually says if someone believes in the Sikh baptism, they are Sikhs" holds no water what so ever within Sikhi.
A baptism is a confirmation to a christian church, a commitment to follow the directions of a particular christian church.
Sikhism is not a sect or denomination of any christian religion, so how can a Sikh be baptised to "confirm to a church".
A Christian can never be intiated into the Khalsa or Sikh religon and be confirmed to the Sikh tenets, and still call himself/herself a CHRISTIAN!
Thus baptism is peculiar to the christian; like circumcision, read with kalma of the Koran is peculiar to a Muslim as is the circumcision of a Jew done by the readings of the Thorah; and the initiation of the Sikh with pahul khanda is peculair to the Sikhs.
A Jew cannot be baptised, nor a Muslim or a Hindu, so like wise a Sikh is NEVER baptised.Sikh scholars of the old have erroneously used wrong terms to describe the Sikh religion many a time.
Perhaps what you mean is a initiated Sikh.A Sikh is initiated in to the Khalsa.He does not become a Khalsa by getting "baptised"-a terminology very very wrongly used to define an initiated Sikh.
I think you may have misunderstood the sentence when it says ""It actually says if someone believes in the Sikh baptism, they are Sikhs".
What it means is rather different than your literal understanding.
A Sikh is a learner that embarks upon the course/path of the Sikhi, must believe that the final goal is to be initiated into the Khalsa.That is what it means.It does not absorb one nor exempt from not under going the initiation simply because one beleives in the final goal; does not mean the one has achieved the final goal.
I terribly BELIEVE in law,but that believe alone has not made me a lawyer, I need to study law and pass the bench marks set, to qualify as a lawyer!Sikhi has its own benchmarks.Because many find hard, are always trying to find ways to by pass those bench marks of Sikhi....and try to find easier paths...considering Khalsahood came at the price of FIVE heads, they simply want to escape keeping their one head intact!!
Unfotunately due to many numbers of factors, many diferent "varieties" of Sikhs have developed in today's world.Many "believe" they Sikhs, simply because they were born in Sikh families, or Sikh families that had lost some Sikh aspect along the way, or have become what they refer to themselves as "MODERN" Sikhs, even though many cannot speak nor hold sensible conversations nor have a modern outlook to life!!
Others discarded the identity of the Sikhs and still convinced /believe they are Sikhs because they feel Sikhi is" internal" and not on the "outside" or external!
Others "feel" Sikh but because their grandfathers & mothers were hindus,but they are all part of Hindus still; as they understand!
Whatever concosions there are, these are simply man made illusions.To truly follow the defined true path of Sikhi, it is at some stage necessary once one has mastered and understood the intricacies of Sikhi in practice and actions and mentally to become initiated into the Khalsa.Guru Gobind Singh has clearly without any doubt shown and directed that.
I hope that clarifies that a Sikh never undergoes any baptism, but initiation into khalsahood!The word Amritpaan transliterated means initiation not baptism.I should have made more use of the words AMRITPAN.