It was noted elsewhere that getting the Class 166 up to 90mph is a struggle at best. I noticed tonight during journey #4, Redding to Paddington, that feathering between power 6 and 7 seems to help a little. I'm submitting that part of the issue is due to wheel slip under icy winter conditions. Too bad Euro engines seem to lack wheel-slip indicators as on some American power units. Try feathering that throttle, fellow engineers, I'd like to compare notes.