I believe (and so does CP) that elastics do not care what type of training is used to improve a skill, just about the levels comparison with its elastically bound other skills. In other words you can use several types of training to improve IS but no matter which one you use the elastics will always be the same.
Also every type of training will be affected by elastics in a different manner for the various skills it improves (and it does makes sense being so).
BBB: 2 (S37 S38); Top tier: 7 (S35 S36 S37 S38 S39 S41 S63); Cup: 9 (S25 S35 S36 S37 S38 S39 S40 S41 S61)