Dave

Collect DTMF does not need EC. I take out your word "probably" because  no need for any dilemma. Interaction between DTMF detector an EC when EC exist is different question and deserve separate  thread.
Although  I am confirming your statement, I can not say "I am voting for you", simple because this is not political forum to express believing to one or other leader or authority.

With respect

koliqi