The case can be made for several people.
In the US, we might say Leslie Peltier [1]. Our friends down under would probably say Albert Jones [2]. The Brits could make a case for George Alcock [3]. And Daniel Overbeek [4] belongs somewhere in this discussion.
So, what are your thoughts?
Can you make a case for one over the other based on anything other than where you live?
Is there anyone else who belongs in this conversation?
Links:
[1] http://simostronomy.blogspot.com/2012/07/leslie-peltier-worlds-greatest-amateur.html
[2] http://simostronomy.blogspot.com/2009/11/albert-jones-interbiew.html
[3] http://martinmobberley.co.uk/Alcock.html
[4] http://assa.saao.ac.za/html/his-astr-overbeek_md.html
[5] http://www.aavso.org/forums/variable-star-observing/visual-observing