Outside their peripheral vision where they can't even catch a glimpse of you is best.
There is nothing I hate more than to have someone stand on my target line trying to get a glimpse of the break.
Yeah the rules of golf kinda don't like that either.
Is there a rule about this?
Thanks,
p
I started going through the rules after I posted my question. 14.2b (Assistance) states "partner" which is someone on the same side (caddie, partner), so that doesn't apply to "opponent". Etiquette is not necessarily a "rule", although enough abuse might warrant a disciplinary action or disqualification - however, there's no penalty stroke, etc. Bummer.
Full shots? Just don't stand in front of me.