in 2012 forum, 2013 forum and in this 2014 forum, I have seen a lot people who are worried/concerned about how VO takes on with their job reference letters, how they check it against fake and fraud docs and how they contact with the concerned persons or how they verify the docs.
I have come across several different situations, like concerned persons have been replaced or changed their contact numbers, company contacts are updated or changed or company itself shuts down or merged, contacts are not reachable at times due to busy timings or different time zones, some times even company phones lines don't respond due to late bill payment or other issues, many times companies are small ones and they shut down due to any reasons, sometimes new person takes the position in previously worked company and doesn't endorse or verify the applicant, the concerned persons are not fluent in English even in basic English and just cant talk except in their native languages, some companies still dont have emails! and bla bla bla so on.......
what I understand is, the cio or VO just cant reject your case if they cant reach the concerned person or department or not able to verify ur reference letter due to above reasons cos these reasons are genuine and very much exists in every part of this world including Canada (not all I agree).
if VO checks and verifies that ur other all docs (educational, language, marriage, children docs, bank statements which are verified at least 4 times during the case, criminal records, medical, etc) are genuine and up to date with everything complete, then they really don't dig so deep in for that case. even if they cant contact or able to converse about ur job reference letter, they don't just reject the case, cos u r fulfilling 95% of else everything so this things gets approved as default (what I understand) for al most all of the cases. even there are applicants who make their own reference letters, design own letter heads, print it out at home or from shops, get it signed and submit and still gets cleared cos there other 95% things are clear! also VO don't have that much time that they re-try and wait until unless they don't get any updates or verification for job references, they have to finish processing thousands of applications and really don't bother to keep on trying and waiting.
then there are those applicants whose docs shows some sort of fishiness, some things up and down, problems with their POF/statements, previous rejections due to any reason (not due to cap filled), fishy criminal records, missing docs, incomplete apps, lack/missed info provided, and so on. so if VO smells and sees anything not going good then they dig in deep.
so people plz remain calm abt this thing, its not a big issue as its been hyped of and created, as long as ur all other docs are ok, just sit back and relax and wait for ur visas.
updated: those applicants who hired a lawyer or listed cic consultant don't have to worry anything, they know their tricks to tackle all of the situations at cio and VO!