On 2016 Jun 27, Martine Crasnier-Mednansky commented:

It is worthwhile revisiting this article considering the strategy described by Müller-Hill B, 1998 was recently reaffirmed Becker NA, 2013, namely, DNA looping in the lactose operon occurs via an increase in local concentration thereby enhancing repression (see figure 1 in Becker NA, 2013).

The authors established the existence of a 2:1 complex between CAP and tetrameric LacI in the absence of DNA. Therefore, one may argue operator occupancy by such complex increases CAP local concentration at the CAP sites. Interestingly, formation of the complex was found to be cAMP-dependent thus local concentration of CAP-cAMP at the CAP sites increases with increasing concentration of cAMP (in the physiological micromolar range).

Because higher cAMP levels (as compared to glucose level) do not interfere with LacI repression (in the absence of induction), it can be inferred formation of a cytoplasmic complex between CAP and LacI would not prevent binding neither to the operator nor the auxiliary operators.

On 2016 Jun 27, Martine Crasnier-Mednansky commented:

It is worthwhile revisiting this article considering the strategy described by Müller-Hill B, 1998 was recently reaffirmed Becker NA, 2013, namely, DNA looping in the lactose operon occurs via an increase in local concentration thereby enhancing repression (see figure 1 in Becker NA, 2013).

The authors established the existence of a 2:1 complex between CAP and tetrameric LacI in the absence of DNA. Therefore, one may argue operator occupancy by such complex increases CAP local concentration at the CAP sites. Interestingly, formation of the complex was found to be cAMP-dependent thus local concentration of CAP-cAMP at the CAP sites increases with increasing concentration of cAMP (in the physiological micromolar range).

Because higher cAMP levels (as compared to glucose level) do not interfere with LacI repression (in the absence of induction), it can be inferred formation of a cytoplasmic complex between CAP and LacI would not prevent binding neither to the operator nor the auxiliary operators.