Yes. Mechanised tunnel boring machines as opposed to hand-worked shields, and different types of lining - pre cast concrete and unbolted cast iron. All this was effectively new to LT, although concrete lining had been used before. The big benefit of tunnel boring machines is that they are quicker and don’t require grouting round the finished tunnel, but they are costly and take time to set up, so there is much value in getting things right. Naturally they are only viable when they can drive on for long distances, the Victoria Line being ideal for that.