Here is part of the discussion from the BECNT-Romans commentary (Thomas R. Schreiner; pp. 413-14):
The second half of verse 9 simply restates verse 9a and elaborates on it, so that the main point is not bypassed. Those lacking the Spirit of Christ do not belong to Christ; they are unbelievers and still in the realm of the flesh. . . Paul is not addressing what believers claim but what they are, and thus the text emphasizes that all believers have the Spirit. The switch from [Spirit of God] to [Spirit of Christ] is instructive, as is the change from the indwelling of the Spirit in verse 9 to [Christ in you] in verse 10. We should not conclude from this that the Spirit and Christ are identical, only that they are inseparable in terms of the saving benefits communicated to believers.
The elders are agreed with this commentary in saying that the two are not the same. But of more interest is what Paul says just a few verses down:
(Romans 8:12-17 rNWT) . . .So, then, brothers, . . . For all who are led by God’s spirit are indeed God’s sons. 15 For you did not receive a spirit of slavery causing fear again, but you received a spirit of adoption as sons, by which spirit we cry out: “Abba, Father!” 16 The spirit itself bears witness with our spirit that we are God’s children. 17 If, then, we are children, we are also heirs—heirs indeed of God, but joint heirs with Christ—provided we suffer together so that we may also be glorified together. (bolding is Bobcat's)
The "so then . . ." indicates that the preceding argument forms the basis for what follows in verses 12 - 17. Yet those elders and the vast majority of JWs (as taught by the WT) will deny that these verses are true in their case and will look at any one who does think they are true as being mentally unstable or under the influence of 'false religion.' This idea, that what Paul says in verses 12 -17 does not apply to them, forms the basis for the refusal of most JWs to partake of the bread and wine at the Lord's Evening Meal in contradiction to Jesus' command to do so.
The WT teaches this lie so as to maintain their control over JWs. The GB say that verses 12 - 17 do apply to themselves. But the rank and file JW is merely a friend or well-wisher who must hang with the GB and do what they say in order to be saved.
Bobcat