Well that was a metric crapton of reading, but here are the nuggets I pulled out of it: (Emphasis Mine as bold and underline)
In the link you provided, I could find nothing to back up your assertion, but found the following sections that back up mine. Since what you linked contained almost 150 pages of information, I didn't read the whole thing word for word. Instead, I did a couple of searches for key words and phrases (such as "prior to" and "in service" and "de minimus" and the below is what I found.
Please copy/paste the relevant sections that support a taxpayer's ability to claim a de minimus deduction for assets BEFORE they are placed into service. I certainly couldn't find anything. If it's true, then it's awesome and will make lots of people happy, but it would fly in the face of most other IRS Tax Code and conventions.
Example 10. Work performed prior to placing the property in service. In Year 1, M purchases a building for use as a business office. Prior to placing the building in service, M pays amounts to repair cement steps, refinish wood floors, patch holes in walls, and paint the interiors and exteriors of the building. In Year 2, M places the building in service and begins using the building as its business office. Assume that the work that M performs does not constitute an improvement to the building or its structural components under § 1.263(a)-3. Under § 1.263-3(e)(2)(i), the building and its structural components is a single unit of property. Under paragraph (d)(1) of this section, the amounts paid must be capitalized as amounts to acquire the building unit of property because they were for work performed prior to M's placing the building in service.
Example 11. Work performed prior to placing the property in service. In January Year 1, N purchases a new machine for use in an existing production line of its manufacturing business. Assume that the machine is a unit of property under § 1.263(a)-3(e) and is not a material or supply under § 1.162-3. N pays amounts to install the machine, and after the machine is installed, N pays amounts to perform a critical test on the machine to ensure that it will operate in accordance with quality standards. On November 1, Year 1, the critical test is complete, and N places the machine in service on the production line. N pays amounts to perform periodic quality control testing after the machine is placed in service. Under paragraph (d)(1) of this section, the amounts paid for the installation and the critical test performed before the machine is placed in service must be capitalized by N as amounts to acquire the machine. However, amounts paid for periodic quality control testing after N placed the machine in service are not required to be capitalized as amounts paid to acquire the machine.
V. Amounts Paid To Acquire or Produce Tangible Property Under § 1.263(a)-2
Section 1.263(a)-2T of the 2011 temporary regulations provided rules for applying section 263(a) to amounts paid to acquire or produce a unit of real or personal property. In general, the final regulations retain the rules from the 2011 temporary regulations, including general requirements to capitalize amounts paid to acquire or produce a unit of real or personal property...
