Would some inspectors say pulling sleeves violate 300-18. This section requires raceway to be "installed complete between outlet, junction, or splicing points prior to the installation of conductors." I have never used them, but could see how they could be used and not damage the wire. Were the ones you used UL approved?
Some say using a C condulet for a soap point instead of actually pulling out the wire is a violation. Calling something a pull point implies using it for a pull point. If the installation of conductors is easier on the workers and conductors without pulling it out, I would go with not pulling it out. Especially on pulls where communication may be a problem and risk someone getting his hand pulled into the conduit.
I've never used a pulling sleeve. I had a job where I looked at using some, but after finding out the cost, I went a different route. Crouse Hinds calls them "pull boxes" and says they are listed under UL standard 886. They are also listed for use in classified areas and can be used as splice points. I would say that if you install a C fitting as a required pull point, then the C fitting must have an opening large enough to allow the conductors to be pulled out at the fitting(see 370-28). If you install it as just a soap point and you have other boxes or fittings for the required pull points I see no problem. Don(resqcapt19)