learning to formate
I would suggest that an important factor in formation flying is being completely familiar with the aircraft being flown, and especially in the slow flight regime.
This is because you will not be looking anywhere else other than at the leader (with the odd glance at the engine T&P and fuel).
A sensible briefing should not overload the student with all the info at once, and initially should concentrate only on the join up and being able maintain the correct position in level flight. Once someone can join safely, break away and rejoin smoothly, plus maintain the correct position without recourse to over controlling with associate excursions, the basic principles are established.
The other 'strange' feeling will be using an element of cross controls to achieve the above, and this should be explained before any actual flying is done.
As alluded to, the ideal mount 'for learning' should be low wing with bubble type canopy (or indeed open cockpit). Once a level of experience has been obtained the principles can be extended to all manner of aircraft types and speeds, with suitable allowances made for high energy/low drag machines.
Leading a formation is a very responsible position and the formation should be treated as an extension of the lead aircraft with (certainly in club aircraft) the knowledge that the wing positions will be needing completely different power settings from the lead, and sometimes will be finely balanced so the the 'outside ship' does not left behind, or the inside position is not wallowing around near the stall. Needless to say there is no substitute to a proper briefing which should also include use of 'hand signals' in case of radio problems. The Tiger Club make it look simple (and indeed the Turbs are an excellent formation mount) but they are a well honed team that train and fly together on a regular basis and therefore are in essence a professional outfit in their operation. Anyone with a serious intent of getting 'informed' would do well to seek some advice from the TC as a start.