I think that depends on what we mean by 'a shoestring'
I also agree that he seems like someone who is going to do something properly if he does it at all, but lay all the eventual costs out (East Stand, training ground, probably refit of concourses and development of footprint of ground) even before you get to 'championship players' (or, dare we say it, 'Premier League players' and it's huge.
There's no evidence we've yet come even close to break even yet and even this year where we've not spent the money some had hoped, we've likely seen a big increase in wages in order to tie down certain players alone.
I don't think we're in for a 'terrible shock' with Sadler, but I think we are in for incremental growth, with player development at its heart and that will take patience and may try the patience of some of us at times.
I think a different point is, when an owner runs a club as their favourite waste of money, however benevolent they may be, there is often a horrendous shock when they finally leave. What I'd hope is that Sadler builds something more sustainable than that whereby our success is down to his work and the structures in place as much as it is down to the brute force of his cash.