As we see it, the key questions is "is there equipoise in respect which treatment is best for the index lesion or lesions (to be defined by the responsible clinician) in the femoro-popliteal segment".
If there is, then we think it is appropriate to randomise the patient and use the allocated treatment for the index lesion(s).
If there are other femoro-popliteal (and/or infra-popliteal) lesions which (may) need to be treated at the same time then we think it should be a matter of clinical judgement as to whether they should be treated and how they should be treated (whether by the allocated treatment or not).
The only proviso is that if a patient is randomised to non-drug technology, the non-index (accessory) lesions should not be treated with a drug technology, and vice versa.
In practice we feel that in the great majority of such cases the patient will have been randomised to DES.
In such DES case, we would ask that accessory lesions, which are thought unsuitable for stenting, be treated with plain balloon angioplasty (PBA).
In the other two arms, which are "PBA +/- bare metal stent (BMS) as clinically indicated" and "drug coated balloon )DCB +/- BMS as clinically indicated" this is much less of an issue (maybe a non-issue in fact) as we would expect "accessory" lesions (not considered suitable for stenting) to be treated with the allocated treatment (i.e either PBA or DCB as per randomisation).
So, in reality it may only be an issue if the patient is randomised to DES.
We will, of course, be collecting in great detail exactly what treatments each person has had.
If we insist that the whole of FP segment is treated with DES (or indeed any stent) then it will inhibit randomisation.
More importantly, it does not reflect real world practice (i.e we do not 'Full Metal Jacket' (FMJ) very often, if at all).
As such, if we do not adopt this pragmatic "real world" approach to the DES arm the trial will not be helpful / impact practice for the benefit of patient.