The SOAP::Lite Guide suggests the following syntax will create an object on which you can call remote methods:

my $soapobj = SOAP::Lite->uri($uri)->proxy($proxy);
my @results = ($soapobj->fn(1), $soapobj->fn2(2));
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In your first example above, I suspect the single quotes are ruining your fun. Perhaps something like this would work better:

my $soapresponse = SOAP::Lite->uri->($uri)
    ->proxy($proxy)
    ->go($doThis)
    ->result();
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I'm not sure how the parser interprets the syntax without parenthesis, but I know the single quotes prevent variable interpolation, which is at least half the battle.