This was what I wrote in my initial post in this thread throwthetellyoutawindow and the trainer names you mention largely fall into the first category.

There are or have been trainers over the years who competed mostly at the top level such as Henry Cecil, John Dunlop, Gosden, Godolphin, Hern, Barry Hills, Stoute and Geoff Wragg. Then there are or have been any number of trainers who have generally had the vast majority of their horses running at a lower level but the problem for Johnston is he has almost always had both and so the range of ability of his best and worse horses is a gaping chasm.

It's very race you will see any of them have runners in sellers, auctions or claimers as Johnston does and some rarely have AW runners too and was my point about Johnston probably in general having the biggest range of abilities of any trainer when comparing his best and worse horses and some punter will back his runner in the sellers and so on just because of his name and from knowing he has trained classics winners before. If Cecil, Gosden, Stoute and others had a horse that proved disappoint and had to drop down to claimer or selling company then usually it would have left their yard before that and will be running in that grade for a new trainer.

At the other end of the scale the likes of Barron and Smart won't have too many if any runners in classics and at Gr1 level and so if one of their lesser lights runs badly it doesn't seem such a massive gap in range compared to their best horses because their best aren't anything exceptional anyway.

Nicholls, Henderson, Mullins and NTW wouldn't have too many run in sellers and claimers either, so maybe David Pipe is in a similar position to Johnston in that he/his Dad have always competed at a lower level too as well as at the top and maybe have had a good few smaller owners that like to have a few horses for fun and have been with the yard for a long time in the way Johnston has those smaller kind of owners also.