I must say that looks impressive, and I am tempted to try it with 2 of mine that are not doing well. But there are arguments against doing this, in Clematis wilt the affected node is often a bottom one, so if you plant deep that node is deeper in the soil and increases the risk of wilt? So what is your instance of wilt has it increased or decreased?
I find to get extra shoots I prune the Clematis after planting mulch with grit and compost and wait.

Hello

Been very lucky iv`e never had a problem with wilt.
I don`t want to disturb the plant to look but i`m not sure if there will be roots from the base of the nodes.

There is something happening to the bases of nodes on other clems (Bijou and Princess Diana) but their not aged plants like these ... I repotted them deeper and completely

I will have to wait till next year to find out ...
They a growing well though and I think there could be flowers soon .. peter

Thanks Peter I am going to try this, so please keep us posted?

Yes, I am going to try it too. It certainly looks as though they might be rooting but I don't know enough about it to give an answer. It would be exciting if they do!

I can't give you the answer you want either Peter, I have no technical knowledge at all :)
I was going to do this with one of mine today but was busy.
I keep looking at the 2 of them and can't decide which one too choose :) I only have 1 empty pot large enough to do this and don't want to go buy another as I would be as well buying a new clematis and this would defeat the purpose, I think.
Re the wilt Drc, please excuse if I have got this completely wrong, is the advice not to cut back the affected stem right to ground level and the plant will recover? This of course would be fine so long as the plant has more than 1 shoot of course. The 2 I want to do only have 1 shoot and no sign of wilt (yet).

Hello Scottish
I would do the 2 ... you will have so many next year you will be selling them ..
Now seems to be a good time in another 4/5 weeks it may be to cold to produce the growth. The Rouge Cardinal now has flower buds ... peter

They look gorgeous, Peter!

Done one of them yesterday Peter, I think the other is just about to produce some buds so will leave that one for now :)
I did take a couple of pics, but will wait to see the finished result and post them altogether.