The Mechanicus is split into two:
One part believes the Emperor IS the Omnissiah. So it's one and the same. That guy would be totally cool.
The other one believes they're separate beings. They're rather disgruntled, but mostly they understand for the Mechanicus to survive it needs the Imperium.
Now if he started spouting that the Emperor and the Omnissiah are separate beings and that only the Immortal Emperor is worth worshiping and that Omnissiah fellow can bite it? Good question.
I'd still like to think that he'd still be accepted by group A (as an apple is still an apple even if you call it an Orange) and still scoffed at by group B.
One part believes the Emperor IS the Omnissiah. So it's one and the same. That guy would be totally cool.
The other one believes they're separate beings. They're rather disgruntled, but mostly they understand for the Mechanicus to survive it needs the Imperium.
Now if he started spouting that the Emperor and the Omnissiah are separate beings and that only the Immortal Emperor is worth worshiping and that Omnissiah fellow can bite it? Good question.
I'd still like to think that he'd still be accepted by group A (as an apple is still an apple even if you call it an Orange) and still scoffed at by group B.