WHY,on God's green earth, (and I emphasize 'green'),
would ANYONE, (besides a golf course), want to cut
their grass down to 3/4 of an inch???????
I cut mine down to 2 1/2 once it reaches 3 or 4.
We have had very little rain, but my lawn is the
greenest in the neighborhood. And no, I don't
water my lawn.

WHY, because hybrid bermuda performs best when cut at 1" or less, duh. Bermuda grows horizontally when the right cultural practices are used. Weeds and fungus don't stand a chance at this height. I don't use any more water at 7/8" vs. when I used to cut at 1.5". It is very drought resistant. Have you ever seen hybrid bermuda at 2.5 inches? It gets very thin, stringy and weed ridden.

Before you invest in a more powerful mower, make sure the blades are sharp on the one you have and you are mowing with the catcher rather than mulching.

Tif 419 is very dense and builds up thatch rather quickly, so sharp blades and picking up clippings is important.

I suspect, however, that the real problem is that you have too good a grass for your terrain. 419 is meant to be kept low and mowed with a reel. Therefore, leveling and filling over a period of time may be the only real solution.

Best Wishes--Carl