I almost hate to say it, but I managed to sit through all six episodes of The Web Planet without noticing very much in the way of incident or engaging very much with the story. I think I had much the same reaction to the novelization.

What interests me about the tie incident is that it breaches continuity; Coal Hill is set up in An Unearthly Child implicitly as an advanced comprehensive, without uniform, and possibly with mixed ability classes too. (Perhaps Waris Hussein, at least, was thinking of Holland Park Comprehensive, as his mother lived in the area, as did Jacqueline Hill and David Whitaker). The 'school tie' refers to a different model, though probably one more familiar to the programme's audience, of uniforms and grammar schools and secondary moderns.