Not offering Tahiyyat-ul-Masjid for anyone who enters the Masjid while the Salah is being established

Q 2: Our regular Imam (the one who leads congregational Prayer) always enters the Masjid (mosque) from a door which is next to the Mihrab (a praying place to the front of the mosque usually used by the one who leads congregational Prayer). He does not pray Tahiyyat-ul-Masjid (two-unit Prayer to salute the mosque). It is worth noting that the concerned Imam does so in all obligatory Salahs (Prayers) though the Masjid is usually not crowded. What is the ruling on such doing? (Part No. 6; Page No. 142

A: It is permissible for the Imam, or anyone else, to enter the Masjid from any of its doors. In addition, if Iqamah (call to start the Prayer) is being pronounced as the Imam is entering the Masjid; he will not be required to pray Tahiyyat-ul-Masjid. A proof for this is a Hadith in which the Prophet (peace be upon him) said: when Iqamah is done, no Salah 'Prayer' is to be offered 'in the Masjid' other than the obligatory prayer. May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.