Ouch buthurt much?
First of all I think its more than safe to assume HE had NO knowledge of electrical systems just by the fact that he stated peak voltage as a meaningful measure. If you don't think so, you are just as ignorant (in the amount of knowledge sense, not the insult sense) as him!.
And it matters not, Battery amp hours are given at 12 volts. Yes like I said the efficiency goes down the higher the amp over less time, but thats how it works and thats how people ride around getting what should be 120 and 200 amps of alternation generation from a 90 amp alt.
Tell me, since I'm the know-it-all and should spread the opportunity to depart this amazing knowledge you apparently posses...
How, in ANY way, Is discharging more than a normal load on an power generation source bad for that source? Do this windings start saying "F U, i'm going on strike?" //content.invisioncic.com/y282845/emoticons/laugh.gif.48439b2acf2cfca21620f01e7f77d1e4.gif
Now is it bad for the battery? Sure, because every time the battery charges and discharges Ions are lost, and current delivery becomes less efficient. That said, current supplied by the alternator declines over time too but no more in an amp suppling 50 amps than in one suppling 20. because alternator current is constant based on RPMs not draw.
A batteries current supply is regulated by that very current draw, and alt is regulated by engine RPMs.