Use 2, 3 or 4 HDD heads to decrease radius and head seek time

I think I have an idea, and I would like to share it with you. In case it’s useful, please, feel free to use it.
So my idea is to decrease (up to 4 times) seek time of the magnetic head in HDD. To do so you should develop HDD with two (or up to 4 heads) in opposing corners. Each of those heads would seek only half (or fourth) of the platte’s radius, thus decreasing distance it would travel, and theoreticaly decreasing seek time (like short-stroking). For example “upper left corner” head will seek only outer half of the HDD’s platter, while the “lower right corner” head will seek only inner half. Decision of which head is used for accessing given sector is made accordingly to it’s track number. If it’s less then half ot maximal track number, access it via head No.1, else use head No. 2.
Additionaly you could implement algorhytm for even faster access, using independent seek for both heads.
And finaly, having redundant number of heads, would give you an opportunity to deal with specific class of damages - ones, concerning damage in one of the heads, but not in the platters itselves. If such damage occurs, you could park deffected head, and use the other one, allowing it to cover full platter radius (like in regular HDD).

You join an idea I thought about 3 years ago : a set of three arms for heads ; one arm for reading and writing fat or whatsoever works like a fat, one arm to read sectors from “source location”, and the third to write sectors to “destination location”, in case of a big move, such deffragging software does. My idea differs from yours on this point : every three arms can seek all the cylinders, offering complex access, and giving full stream data extraction even with deffragging at the same moment. The big difficulty : developping routines for NCQ that ensure proper and optimized moves for the three arms.

I thought also  about a very fuzzy improvement : putting a small air-pump to make partial vacuum inside the enclosure, in order that arms seek at high speed, without too much power to throttle them. 4 quadrant speed variators could also drastically reduce electric consumption when seeking like fools, but perhaps this method of driving heads motors is allready in use …