If the foreign experience is more than 1 continuos year in NOC 0, A, B category, it may satisfy your FSW eligibility so you may not able to apply under CEC.
If you have no problem on gathering enough points to get ITA without it, why would you want to put them in your application as you will need to prepare all documents for those such as LOE, pay slip, and so on.
It's hard to satisfy only CEC not FSW by the work experience itself. If you have more than 1 year continuos work experience, then you qualify to FSW no matter it's Canadian experience or not.
For example, if you worked 6 months at A company and another 6 months at B company in Canada in last 3 years and you were unemployed for 3 months between A and B, then you will only qualify CEC as FSW wants you to have at least 1 year continuos job in NOC 0,A,B.
From what people have said on this forum, if you put '0' as Proof of Funds then you will meet only CEC. Never did this myself so I can't say for sure if it works.
No, that is not exactly correct. There are three FSW requirements that do not exist for CEC.
1) Proof of funds (waived with arranged employment/valid job offer; not required for CEC)
2) Foreign work experience (optional for CEC to gain additional EOI points ).
3) ECA is required (optional for CEC to gain additional EOI points ).
If you meet these requirements, you will get the ITA for FSW instead of CEC (by default).
If you actually do have a valid job offer with the extra 600 points, you definitely want to keep that. In that case, you could safely drop the ECA, proof of funds, and/or foreign work experience and still have enough points to receive an ITA under CEC.