Based on your recommendation, I'll not submit client letter considering the probable trouble with that (my employer relationship/reputation with client etc & also termination risk).
This was not my recommendation, I think it is a good thing to include the client's letter but you must also have your employer's letter (in which case there'd be no chance of confusing you with self-employed). But I am not in your shoes and am not aware of the risks you describe.
Until last year, Checklist in Section 6 Work Experience suggested the following...
"If you cannot provide a reference from an employer, provide a written explanation and any documentation that would support your claim to such employment and provide the information as set forth above"
But this year's CEC checklist Section 10 "Work Experience in Canada" doesn't have this. But at the at the top of checklist it says...
"If you're unable to provide any of the requested documentation, include with your application, a written explanation with full details as to why that documentation is unavailable and any documentation that would support your claim. If your application lacks any of documents without reasonable justification, it will be returned to you or in certain circumstances could result in the refusal of your application."
So I'm puzzled. Will Case officer still consider the application without a proper employer reference letter? I'm hopeful that Case officer considers other aforesaid documents (T4 etc) in lieu of reference letter.
T4s are required IN ADDITION TO the reference letter, they can't replace it. Get that out of your head. The change in instructions was made because too many applicants took that as a license to apply without the Letter of Employment. CIC gave them an inch, they took a mile... and were refused as a consequence. As reported on this and other boards, the lack of an employer's reference letter will almost certainly result in a refusal, at least as currently being processed by CIC.
Consider this - any one or even several of those documents are possible to fake, therefore CIC requires multiple sources of evidence that can easily be verified. If you wanted exceptions to the Letter requirement, you'd in effect be expecting CIC to launch its own investigation, processing times would expand by several years, costs would go up, etc... That would be bad for all of us.
