Food for thought? Yes indeed, and here are some:
Positive thinking as a method of control? I can see how that works on the physical plane. Certainly it is a standard technique of the BKWSU to control "students": BapDada says
Start thinking in a positive way, and the negative will automatically finish
and so they refuse to listen to any criticism, let alone respond to it or act on it, no matter how valid or constructive that criticism may be. This is their default behaviour, and any exceptions seem only to occur under extreme and persistent provocation.
However, in spiritual terms it makes sense to think positively. As BapDada says:
light finishes darkness. If you continue to think "dispel the darkness, dispel the darkness", then you will become disheartened.
In other words, be radiant, and the nasty stuff will not stick to you. A practical example is the teaching to avoid operating consciously in the astral planes, as there is much danger there, and no benefit, while a high spiritual stage will simply make you immune to anything astral (or physical). Why labour and struggle, when there is an effortless alternative?
But, on a more mundane level, blind positive thinking, as practiced and taught by the BKWSU is akin to the myth of the ostrich hiding its head in the sand to avoid dealing with uncomfortable reality. In a word, denial. This causes only harm. Problems, obstacles, troubles of any sort, have to be faced head on, understood, and vanquished. Sticking your head in the sand may make you feel more serene for a short while. But nothing has been dealt with. Whatever you are hiding from will come back to haunt you again, when you finally take your head back out of the sand. This level of "positive thinking" solves nothing, and simply stores up problems for later.
The video posted by maria cites the example of someone losing their job in the corporate world, and being advised to think positively to "attract" another job in the corporate world. This might apparently work, as a positive attitude will more likely lead to applications being completed and posted, and to interviewers being impressed. But nothing is solved, as the real problem was being involved with the corporate world at all in the first place! Instead of seizing a great opportunity to free oneself from the chains of corporate slavery (fully analogous to BKWSU slavery), the sucker (oops I mean victim) jumps from the frying pan into the fire... and gets burned even worse.
The problem is not positive thinking, but shallow thinking.