Yes, I do hog my Section D gelding because he has sweet itch and he does look fantastic with a hogged mane. I can only show him in M and M anyway because he isn't registered.
i knew a gorgeous dark bay section D when she was being broken. Then someone baught her as a 'showjumper' and cut off every bit of hair they could find. She also had about a 1.5 foot 'bridle path' at one point (scissor-happy)
She looked very tidy and nice but could hardly tell she was a sec D. IMO she looked better with her lovely long mane and tail, would have won every welsh/ M&M class she went in.
Guess thats not very helpful actually reading back but maybe you'l find some use in it. It depends what you use them for. If no good reason for hogging, leave a nice mane especially on any welshie theyre lovely that way.
No, never. My last boy was a Welsh D, he had sweet itch and I still refused to hog him, he wouldn't have looked right without a mane (plus it didn't take that much extra maintenance).