WS, I do not doubt from your experience, but I think that as a former 11' and 12' IMG Match participant for surgery, I can share my two cents. I did extensive research about ECFMG requirement timelines, since I didn't get mine until January 11'. IMHO, programs, at the very least, require it at the time of ROL - not having the requirements for its expenditure only, but the certificate itself. The risk that underlies with the former is that they can match a certificate-less IMG who by many reasons (especially with an institution as ECFMG) can have his/her certificate delayed, precluding him/her of starting residency on July 1st, as certification is a must for GME at any ACGME program. This is very bad for programs and has happened in the past. ECFMG issuance is a cumbersome process with extremely strict requirements and it takes around 4-6 weeks to have it mailed to you once all documents are submitted and approved. At the moment one document has a flaw, the process is delayed 4-6+ weeks. The vast majority of programs require it at time of application or somewhere in November, when submission deadlines are reached.
My statement from previous post, regarding ECFMG as a must by the time of applications, comes from my (and many other IMGs) experience that 90% or more of programs paper-trash IMG applications without the certificate, reason being too that there are just too many solid applicants who have it. They may have paper-trash my application for many other reasons (mainly by the fact that I am an IMG), but on 11' I was certificate-less and got a prelim spot by miracle. On 12' I had a certificate and had to cancel interviews. Even though, if you get invited to a program that does not require it, being certificate-less during interviews and being questioned about it on Nov-Dec-Jan, gives the program a reason to not rank you. This is what I felt when I was questioned about it. It is not enough to tell them 'hey, I will be getting it on Feb, or May when I get my diploma or clear step 2 CS or wathever'. If there is such a flexible program with these issues out there, I would like to know.
Hence, my advice stands. Your chances, which a priori are small, become dramatically reduced if you apply without a certificate.