Can assignment meta-operator be combined with feed operators?

[Dave Whipp]

S06 says that we need to say "eager" if (@in === @out). So:
  @data ==> eager map { $^x + 1 } ==> @data.


Is it possible to modify a feed operator using the assignment 
meta-operator described in S02 and, if so, is the "eager" implict?

  @data ==>= map { $_ + 1 };