I took the time to test the proposed changes and their impact. My findings are as follows:
Summary
The proposed changes take the uniqueness of the Deception Assassin and Infiltration Shadow classes away to a major extent. Furthermore the dps reduction impact is huge (or alternatively takes away the classes uniqueness) - apparently a lot more than Bioware expected. In detail:
Deception Assassin and Infiltration Shadow
Both classes shine in three areas:
Stealth Melee Burst Damage Melee Execution Damage
For PvE we got the following roles:
Spot DD Off Tank Stealth Mez Stealth Rez
For PvP we got the following roles:
Defense of captured points 1 versus 1 Execution of targets (have them dead before the pesky heal drops in) Take enemy healers out of the game
Deception Assassin and Infiltration Shadow in their roles in PvE
Overall the strength of their class leads to issues in their roles. With their high burst both classes can easily receive aggro from boss monsters, while the execution of a high dmage output is difficult and demands a lot of knowledge, positioning and extremely fast reaction (to maintain the dps output). All this, while the dps output is RANDOM. With a lot of luck both classes can achieve around 15K dps in the first 20 seconds. Without luck they achieve around 11K dps in the first 20 seconds. This drops down to app. 9.3K dps after the burst phase until the execution phase starts (30% health or less of the target), where it can rise again around 10.3 K dps.
Bottom line: the shorter the length of a boss fight, the more both classe shine (shorter middle phase). The longer a boss fight and both classes start to perform increasingly worse (in dps output). Or in other words, chance plays a lesser role since the the amount of random events even out on the long run.
All this is also reflected in parsely leaderboards, where both classes shine on 500K and 1.5Mill dummies, but udnerperform at 4Mill dummies.
As a matter of fact both classes are well within the dps range and even underperfom compared to e.g. Marauders in Melee (300+ dps less).
Deception Assassin and Infiltration Shadow in PvP
In PvP it is up to the player to let the classes shine. Being in the midth of an even Melee battle usually kills both classes quite fast - despite their defs. It is crucial to avoid long Melee battles toe to toe with differing opponents of similar skill.
A player aiming for first strikes (deliver their burst damage) and then switch to targets on low health (execution damage) - such a player sure lets both classes shine. Also in single point defenses in 1vs1 and even 1vs2 situations both can shine: CC abilities + burst and execution damage.
Impact of proposed changes of Deception Assassin and Infiltration Shadow
The suggested changes do several things at once:
Removal of high burst damage Removal of high execution phase damage Keeping the RANDOMness of both classes
The changes to Discharge basically remove the burst damage opener. Yet there are still alternatives with Maul, which in return break power management of both classes for long term dps output.
The reduction of execution phase damage from 5% to 3% coupled with the other changes basically brings these classes to a similar level like other classes, which also offer exection phase damage increases.
Overall
So these changes basically take away the uniqueness of both classes. Yet first results suggest, that a high damage output is still possible (yet even more random but without burst and execution phase advantages) - making these changes void. This in return requires them to use Force Cloak on cooldown (which we already did to maintain high dps) and maybe even respecc to increase power regeneration. As a result these changes also take away the uniqueness as stealthers in PvP.
So a possible result of these changes is that both classes are basically the inferior version of a Annihilation Marauder or Sentinel Watchman - except stealth is slightly better.
Or in other words: thee changes take a unique class out of game - a change is not really needed.
Alternative changes for Deception Assassin and Infiltration Shadow
Apart from above reasoning, there is a understanding why someone woudl assume both classes "overperformers" (which is actually due to RANDOMness). As such a proposed different change would be:
Remove chance based procs and set their respective chance to 100% (always procs) Reduce damage of Maul (as well as the Maul based proc), while increasing the position based damage (from behind).
These two changes would decrease the dps output overall (snce the high dps parses are actually due to well-placed Mauls in a rotation), lead to a more consistent damage output, while keeping the classes uniqueness and even strenghtening the "Assassin style".