Sounds to me like a controller with too much time and not enough airplanes. Just so everyone here knows what standard controllers are held to, here is an excerpt from the 7110.65V Air Traffic Control Manual. Note the note.
2−4−3. PILOT ACKNOWLEDGMENT/READ BACK
Ensure pilots acknowledge all Air Traffic Clearances and ATC Instructions. When a pilot reads back an Air Traffic Clearance or ATC Instruction:
a. Ensure that items read back are correct.
b. Ensure the read back of hold short instructions, whether a part of taxi instructions or a LAHSO clearance.
c. Ensure pilots use call signs and/or registration numbers in any read back acknowledging an Air Traffic Clearance or ATC Instruction.
1. ATC Clearance/Instruction Read Back guidance for pilots in the AIM states:
a. Although pilots should read back the “numbers,” unless otherwise required by procedure or controller request,
pilots may acknowledge clearances, control instructions, or other information by using “Wilco,” “Roger,” “Affirmative,” or other words or remarks with their aircraft identification.
b. Altitudes contained in charted procedures, such as departure procedures, instrument approaches, etc., need not be read back unless they are specifically stated by the controller.
c. Initial read back of a taxi, departure or landing clearance should include the runway assignment, including left, right, center, etc. if applicable.
2. Until a pilot acknowledges a controller’s clearance or instruction, a controller cannot know if a pilot will comply with the clearance or remain as previously cleared.
“Climbing to Flight Level three three zero, United Twelve” or “November Five Charlie Tango, roger, cleared to land runway four left.”
2−4−9. ABBREVIATED TRANSMISSIONS
Transmissions may be abbreviated as follows:
a. Use the identification prefix and the last 3 digits or letters of the aircraft identification after communications have been established. Do not abbreviate similar sounding aircraft identifications or the identification of an air carrier or other civil aircraft having an FAA authorized call sign.
b. Omit the facility identification after communi- cation has been established.
c. Transmit the message immediately after the callup (without waiting for the aircraft’s reply) when the message is short and receipt is generally assured.
d. Omit the word “over” if the message obviously requires a reply.