Strange, most probably unjustified, codoc mismatch for S4 method with one argument plus '...' (re-try)

On 12/15/2012 06:26 AM, Martin Morgan wrote:

In ?setMethod there is this paragraph

     It is possible to have some differences between the formal
     arguments to a method supplied to 'setMethod' and those of the
     generic. Roughly, if the generic has ... as one of its arguments,
     then the method may have extra formal arguments, which will be
     matched from the arguments matching ... in the call to 'f'. (What

and in practice the expectation is that if a generic has formals x, y, and
..., then a method will have formals x, y, and possibly additional arguments.

Thank you very much for your detailed and very helpful reply, Martin! I now
understand that all formal arguments of the generic should be included in the
list of arguments of methods even if one of them is not needed. My rationale -
obviously, I had not looked into the docu well enough - was that I need not
declare arguments that were not used in the function body anyway. Since I have
not gotten a warning so far (until I experienced the case in my initial
posting), I thought this was right.

So, am I right that the problem is rather that the first and third of the
definitions

setMethod("dummyMethod", signature(x="matrix", y="missing"),
          function(x) {})

setMethod("dummyMethod", signature(x="data.frame", y="missing"),
          function(x, ...) {})
setMethod("dummyMethod", signature(x="list", y="missing"),
              function(x, sel=NULL, ...) {})

do NOT result in a warning although they are not correct either while the second
one correctly results in a warning?

Thanks and best regards,
Ulrich