I thought Ortho Effect is well known, and hence refrained from explaining it in my words because there are professors and books that can explain it much, much better.
But yes, I was wrong. Well then, if its not the explanation, then fact is, a methoxy substituent at ortho position does not cause any Steric Inhibition of Resonance effect. Yes, I read from the wrong book, I guess.
I think there are many effects operating, but maybe there is one particular effect which is very strong, and wins all over the others.
I will think and reply.