Walk-around controls

[nachoman]

When did the first walk-around model train controls come out? I like reading older issues of model railroader, and I have noticed at some point between 1970 and about 1980, the style of layout began to change. Layouts slowly evolved from a more rectangular with access holes shape, to an around-the-walls philosophy. Track plans evolved from a series of interconnected and overlapping loops to a linear style that is more common today. Layouts also got bigger. I used to think that was because houses got larger, people got more disposable income, more ready-to-run items meant lest time in the workshop, or a bigger emphasis on realistic operations. But looking at Gary's layout something dawned on me -

That style of layout would be pretty darned inconvenient without walk-around controls!

When did walk-around controls become readily available? Was this a main contributor in the change in layout style? I am sure people made their own hand-held rheostat controls fairly early on. But there was no "memory", so there would still need to be a long wire. When were the first commercial hand held controls available? I can't imagine they would have been made before transistorized throttles became available - mid 1960s?