Peter,
You are 100% correct.
I've quite a few tied with red game hackles and although they are more resilient (tailnippers can shredd these too eventually) they don't give me that warm feeling that pheasant tail fibres does.
As with the majority of flies I use the expensive bit is the hook (and bead in this case) and if the fly requires redressing after 1 good fish, 4 nice fish, 6 lovely fish, whatever - it's not an issue.
I do regularly check the tails as I've genuinely found that the amount of offers reduce if there is no tails.
Great flies though
Iain