DD> When we planted our tomato seedlings, my huband buried a 2
 DD> litre plastic pop bottle, punched with a few holes
I do the same thing, "DD", and here in Okla., it is very helpful.  Though 
we've had good rain, this year, it usually isn't the case... and I share your 
belief, about deep watering... Roots go where the water is.   If the water 
source is in the surface ground (say the top 3-6", the roots will be, also... 
water available 12- + down, you'll get those deep rooted plants that do so 
much better at withstanding poor conditions of summer months.
cheers,
wls
---
---------------