Whilst Clag has improved from day one, in the way it transforms from start up to running, can we also have the correct physics, ie smoke not launching straight up in the air. In reality, only the slightest bit of a breeze or movement from the train forces smoke an any particular direction. It dosent work the same way as a steam loco. Thats why we have dirty roofs on HST trailing power cars and platforms being shrouded in fumes, for example. REF Armstrong powerhouse clag factor in TS.