Recently is has been proved that every Minimalist grammar can be converted into a strongly equivalent single movement normal form such that every phrase moves at most once in every derivation. The normal form conversion greatly simplifies the formalism and reduces the complexity of movement dependencies, but it also runs the risk of greatly increasing the size of the grammar. I show that no such blow-up obtains with linguistically plausible grammars that respect common constraints on movement. This establishes not only the cost-free nature of this normal form for realistic grammars, but also that the known restrictions on movement greatly reduce the range of licit movement configurations relative to what unconstrained Minimalist grammars are capable of. Moreover, this work constitutes a first step towards a quantitatively grounded view of movement
