Multiple Custom validation callbacks only work if using "required" rule?

[eluser]tonanbarbarian[/eluser]
this seems to be intensional (although I cannot see why but the logic of it may escape me at the moment)

from Validation class line 278:

Code:

// If the field isn't required and we just processed a callback we'll move on...
if ( ! in_array('required', $ex, TRUE) AND $result !== FALSE)
{
  continue 2;
}

so if the field is not required and a callback didnt return false it will stop processing rules
might want some of the developers to explain the logic behind this I guess