Tom Rosenbauer's book is useful for anyone starting to fish for wild brown
trout in West Country rivers
He has this to say about the roll cast:
Most anglers think the roll cast is used more often than the overhead
cast in small streams, but its utility is overrated, ...It's hard to make
the roll cast as accurate as a short overhead or side cast, and accuracy
is one of the prime tenets of small-stream trout fishing.
Tom is right. It can be difficult to make a roll cast that lands a fly
accurately. And accuracy is important on our small rivers. Hopefully this
page contains some pointers to overcoming the problem.