If you are pulling wire, pull another ground wire too. You can't have too many grounds.
In the old days before three-prong grounded outlets, ground straps were considered nice, but not essential. Thankfully, those days are long gone. But in retrofit jobs or remodels, you may still encounter circuits that are not properly grounded. You must bring those circuits up to code.
The National Electric Code (NEC) has strict language for grounding. Grounding is the norm. Redundant grounding and even double-redundant grounding is frequently called for. Grounding Codes are covered in NEC Article 250.
It doesn't matter if you are running EMT or any metal jacket conduit, you must pull a ground wire. For the technician in the field, just follow one simple rule: If you are pulling wire, pull another ground wire too.