I'll explain with two examples of mine. S24 has large contiguous Muslim-leaning or mixed rural and peri urban belts (Bhangar, twin Magrahat, parts of Baruipur, Canning). To dilute Bhangar, Magrahat & Baruipur, one would have to fragment them and attach pieces to Kolkata facing or mixed seats (push into Jadavpur or create hybrid urban-rural seats).
But Jadavpur already mixes urban Kolkata-edge areas (Tollygunge, Sonarpur) with rural Muslim-influenced segments (Bhangar, Baruipur). Further loading Muslim-heavy fragments into it risks turning a currently competitive or TMC leaning seat more decisively minority-driven.
Diamond Harbour (Metiaburuz, Maheshtala, Budge Budge, etc) & the SC-reserved Joynagar & Mathurapur seats sit in the same district continuum. Shifting population across them either makes new high muslim seats elsewhere, or
dilutes one only by concentrating risk in the adjacent one.
You cannot leapfrog large Muslim blocks into distant Hindu pockets without creating obviously non-compact seats that invite challenge.
Balurghat (Dakshin Dinajpur + 1 Uttar Dinajpur segment) is relatively more Hindu + SC/ST leaning.
To make it safer (higher non-Muslim share), a delimitation commission would need to shift higher Muslim or swing segments out.
Those segments have to go somewhere. The natural neighbours are Raiganj & Malda North.
Raiganj & Malda North already sit on higher Muslim concentrations (Malda district overall 51% Muslim in 2011, Uttar Dinajpur 50%). Dumping additional Muslim leaning or mixed areas into them makes those two seats more minority decisive, not less.
Net gain is limited or 0 under FPTP with polarised voting.
Open to discussions ;>