I am not sure I agree and personally would not use Coffee decaffienated using the Methyl Chloride process.
an overview of the various processes here
http://coffeetime.wikidot.com/decaffeination-processes
Looking more deeply at Chloromethane (Methyl Chloride)
http://www.oecd.org/dataoecd/24/7/31745698.pdf
Is an interesting example of how difficult it is to destroy the product in certain situations and also how under certain conditions, it can react with other compounds
e.g.
Options for disposal
Remark: "A potential candidate for rotary kiln incineration at a
temperature range of 820 to 1,600 deg C and residence times
of seconds for liquids and gases, and hours for solids. A
potential candidate for fluidized bed incineration at a
temperature range of 450 to 980 deg C and residence times of
seconds for liquids and gases, and longer for solids."
and
Its presence in municipal waste landfills may
suggest that consumer products containing chloromethane were
landfilled (e.g., propellants for aerosol cans). In a study
of the products of initial combustion using mixtures of
chloromethane under simulated incinerator conditions,
chloromethane was destroyed under oxygen-rich conditions
(Taylor and Dellinger 1988). Under oxygen starved
conditions, however, chloromethane can combine with other
components of the mixture to form, among other compounds,
chlorinated ethanes,
No be clear, in the second example I am not suggesting that other compounds can be formed during the roasting of coffee, but in a sense, it's often done under Oxygen starved conditions (depending partly on roaster and of course the substance is in (not on) the bean.
My view is this is not a chemical I would want to see used on a food product that I am later going to consume. Indeed mabye all the damaging products are removed by roasting/possibly they are not!